There are 21 possible numbers Maura could have called at that New City destination on her cell log. That much I got, based on readily available prefix data by area code. But I missed something.
A sharp person in our group who goes by AWOLNATION (who only rarely posts) also got the provider data for each number. It breaks down like this:
Verizon - 11
Sprint PCS - 2
Land Lines - 8
Many thanks for this great contribution, AWOLNATION.
We can surmise that Billy had a Sprint PCS number. This because: (1) the affidavit that police used to obtain Maura's cell records shows that she had a Sprint PCS number, and (2) Sharon said she added Maura to the Rausch's family plan. (If anyone has a clean, definitive source for this, I would like to see it.) There is no guarantee that Billy was on the Rausch family plan, mind you, but it seems likely. The following analysis stands, either way, although it would change a little it he were not. To proceed, I assume he was.
This above data is subject to a caveat: it is from 2012. The wireless numbers could have changed providers since 2004, perhaps multiple times. Under the Telephone Portability Act of 1996, if you change service providers your former carrier is required, upon your request, to release it to your new provider. Providers make that process of requesting easy for you.
Transfers like that, however, probably evened out over eight years, in proportion to the overall market dynamics as reflected in the 2004 data (above), which is consistent with overall national market share data (in most markets Verizon has a lot more accounts than Sprint). Thus the 2012 data gives us some idea of the mix in 2004 in New City. As for the landlines, they likely were still land lines in 2012, even if providers changed. Prefixes are usually reserved entirely for wireless or entirely for land lines. Once established, this is logistically difficult (and expensive for the providers) to change. The land line providers don't matter to us because the only specific identities we have to consider are Julie and Billy, neither of whom were not physically in New City that night.
Thus viewed, the data supplied by AWOLNATION shows that among the 21 possible New City numbers Maura could have called, there were way more Verizon wireless than Sprint PCS numbers and there were around 35-45% land lines.
This realization data puts a healthy constraint on the intuitive appeal of New City's proximity to West Point. Ironically, by so doing, it buttresses the reasoning of the original topic post (below), to the effect that Maura's New City calls on the 5th were to Julie.
To see that, scratch your chin a moment regarding the following three facts:
 The Department of Commerce defines the NYC metro area to include the entirety of New York City, as well as areas outside the city connected to its infrastructure (public transportation, trucking patterns, commuting patterns, supplier-retailer relationships, cultural affiliations, etc.) This includes the Lower Hudson Valley and the entirety of Rockland County (where New City is located). West Point lies about 5 miles north of the thus defined NYC metro area. This means that New City is geographically, demographically and culturally considered to be a part metro New York City. It is less than 25 miles from mid-town Manhattan and only 15 miles away from Yonkers, the first municipality north outside of the Bronx, NYC's northern-most borough.
 Metro NYC contains 19 million people as of the 2010 Census. Rockland County contains 315,000 them. The population within 22 miles of New City, therefore, likely is somewhere between 6 and 10 million people, as it includes significant portions of West Chester County as well as half of New York City. Julie and Billy, on the other hand, total 2 people. Moreover, all of those millions of people live closer to New City than Billy and Julie did while at West Point.
 Many students at UMASS, and lots of people generally, hail from or once lived in this highly populated area around New City. According to UMASS's undergraduate admissions page, of all states from which their undergraduates hail, New York sends the most. New York state's population is concentrated heavily around New York City (thus near New City), the most populous city in the country. On the numbers, Maura easily could have had an as yet unknown new boyfriend or new friend at UMASS or living Amherst. That person could have once lived in this region or had relatives who do and got him or her a cell phone. In fact, for all we know, Kate - native of Saratoga Springs, NY - had an aunt 2 hours south on the western side of the Hudson River Valley (i.e., in metro New York City) who got her a cell phone for college.
 Meanwhile, amid all those multiple millions of candidates who - based on their proximity to New City - might have owned the one of the 21 possible numbers Maura called, only 13 (the cell phones) could possibly have been Julie. Only two (the Sprint cell phones) could have been Billy.
Bottom line: while relevant, the proximity between New City and West Point - statistically speaking - is not as significant as it is intuitively appealing. That can bias us, in a way that creates a subtle form of circular reasoning.
That circular reasoning goes like this: "she and Billy were on the rocks" >> "yep, and then she took booze and a stuffed animal toward a resort" >> "well then, she was getting out of dodge to get away from him, get her thoughts together and maybe break up ... pretty obvious, case closed" >> "oh, she called New City right before she got upset? Hmmm..." >> "AHA! New City is only 22 miles from West Point!" >> "see, I told you, it's all about Billy."
Yeah, except that within that 22 miles radius there are another 6 to 10 million people.
Economists and quantitative researchers call that "facial validity": something that has so much intuitive appeal that it never gets investigated or analyzed on rigorous terms and lies there, unseen and incorrect, distorting your conception. (Sometime, by the way, if you want to tell someone they are drinking their own bath water but don't want to argue the point with them, just say "your point facial validity." It technically says their thinking is too shallow, but it sounds flattering. It can come in handy on ... eh, leave it alone John.)
Which brings us back to the original reasoning of this topic post. Without being premised on the New City destination of the calls, or on any theory of why Maura bolted, it shows that the facts we have in hand point hard and strong to Julie, who - only as a secondary matter in that analysis - could have had a New City number. That is, the reasoning does not start with the idea that it had to be Julie or Billy and it is not driven forward by a thesis about why Maura bolted. Compare that to the circular reasoning discussed three paragraphs above.
HOWEVER, Renner holds us hostage. (Just kidding there James ... mostly). If his source is as reliable as the so far not refuted argument in the original topic post, we have a complex situation to reckon with (as discussed in original topic post). One of our group - Debbie - has proposed an idea that could resolve that back to a simpler (and therefore more probably true) thesis. But until we know about Renner's source (or at least how reliable it is), we can't move forward.
JAMES! Speak! Please!______
Today, I go out on a limb. And I challenge Renner in so doing. Fingers crossed.
In discussing the upsetting call, two conclusions - as follows - often are stated, although not universally.
(1) The upsetting call was with Kathleen. UMass police Lieutenant Robert Thrasher has been quoted or referenced by multiple journalists - including Boston Globe columnist Brian McGrory in his March 2, 2004 piece "Where Could Maura Be?" - as saying that the call was with "one of Maura's sisters" but that police have "not gotten an answer as to what it was about." This - together with a call to Kathleen being on Maura's cell phone records at 10:10 pm - has led to the conclusions that the call with Kathleen upset Maura. In her 2007 series, for example, Maribeth Conway says that "Maura did not get upset right away," instead beginning to cry three hours later. This indicates that Conway also reached this conclusion. Karen Mayotte's initial (and understandable) confusion in her first statement to Renner about time frames temporarily buttressed this conclusion.
(2) The New City calls were to Billy. This due to the sharp observation by one of our posters regarding New City's proximity to West Point, as well as the oft-discussed thesis that Maura's troubled relationship with Billy was a prominent impetus in her decision to bolt north on Monday the 9th.
I believe that both these conclusions are wrong.
If the call with Kathleen was the upsetting one, the scenario is too improbably bizarre. To wit, they talk for 28 minutes, get off the phone, Maura works and makes other calls for almost two hours, then at some point between about 12:15 am and 1:10 am, it dawns on her that she is devastated, existentially so. She becomes stunned, unable to speak, unconcerned about hiding her cell phone from her supervisor despite it being against regulations, unable to continue working and unable to walk back to her dorm by herself. Her upset was so steeply concerning to Karen Mayotte that she was thinking about ways to stay with Maura that night and made recommendations about counseling. It requires an improbable and complex scenario to conclude that somehow it took Maura two hours to recognize her devastation.
If therefore the upsetting call was with Kathleen, she must have called back later on the desk phone. This is technically possible, but equally unlikely. It is possible because although outgoing calls to numbers off campus typically are not possible on a hall desk phone, incoming calls are. (This because many entities may need to call a dorm's security desk for any number of reasons related to security's function. This includes parents, security colleagues, public health officials, public safety officials, etc.) Still though, it is unlikely that Kathleen later called Maura back on the desk phone, or even knew the number to Melville Hall, or would have had any reason not to simply call Maura on her cell. They had spoken via Maura's cell that night.
As such, you have to stretch a scenario like Play-Doh to conclude that the upsetting call was with Kathleen. The evidence and factual timeline we have strongly suggests it was not a call with Kathleen that upset Maura.
Maura has two sisters. Therefore - unless you think the UMASS authorities are lying or mistaken - the upsetting call was with Julie.
But Maura's cell records are not consistent with this notion, at least if you subscribe to conclusion that the New City calls were to Billy. Did, therefore, Julie call the desk phone? This again is unlikely, for most of the same reasons it is unlikely that Kathleen did, as discussed above. Thus, keeping the scenario in the simplistic likely range, the upsetting call with Julie almost certainly was over Maura's cell phone.
In a January 15, 2012 topic post, however, Renner confirmed that the New City calls were to Billy. The last of these calls is the only call proximate to Maura's upset. It is in fact so proximate that it seems obviously to be the source of the upsetting call. It is also the only one that could have been to Julie, unless she was in Amherst. But as confirmed by Renner, that call was to Billy, right?
I don't think so. Observe that Renner named no source on the January 15, 2012 topic post. As such - and consistent with what he has asked me to do - no source means no fact. In that context, everything I can put on the table now leads to the upsetting call being from Maura to Julie at 12:07 am on Julie's New City cell phone.
Bear in mind that it is just as reasonable to think that the New City number belonged to Julie as to Billy in terms of the proximity of New City to West Point. They both were cadets and in the same class. In fact, it could be the case that West Point - like many institutions - had a deal in place with a New City account and hardware retailer to provide cut rates for cadets. In any case, the sequence of events and known (and sourced) facts described above make it more likely that the New City number belonged to Julie than to Billy.
Even beyond the exclusion of Renner's source, I would go so far to say that the evidence as linked together above is so strong that his source really needs to be validated. For if the above reasoning and his source both withstand scrutiny by our group on the blog, we are left with a difficult, complex and improbable scenario around the upsetting call.
Subtly, the concept of the upsetting call being with Julie is corroborated by the Murrays. We know that the Murrays generally want to dampen public discourse about Maura's life prior to the accident. They themselves so say. Yet Fred and Kathleen have spoken to multiple journalists at relative quotable length on one topic in Maura's personal life prior to the accident: that upsetting call. Specifically they have said, openly puzzled (as indicated their use of the rhetorical wondering aloud) that they cannot understand why the talk with Kathleen about a fight with her boyfriend would have upset Maura. Why talk openly about exactly one facet of her personal life while simultaneously and with some conviction espousing the general theory of - to paraphrase Fred - "her personal life before the accident is irrelevant ... she's missing, just find her?"
Here's why: they have seen Maura's cell records, uncamera-ed (i.e., without the black cover markings). They know who the New City number belongs to. They know Maura was talking with Julie. They probably therefore know what upset Maura. They make an exception in talking about that one facet of Maura's personal life before the accident not to inform but to subtly obfuscate. In this context, the conclusion that the call was with Julie actually serves to resolve a dissonance in the Murrays' stated attitudes about discussion Maura's personal life prior to the accident.
Still another way to see that Julie owned the New City number is to put yourself in the UMASS authorities' shoes. Can you conceive of them asking Julie if she was on the call that upset Maura and her replying "yes, but it is none of your business what it was about?" She would never have saddled that horse at all knowing she wasn't going to ride it, so to speak. It thus is clear they saw her number on their uncamera-ed versions of Maura's cell records.
In other words, the simplest explanation - given what we know (disregarding Renner's unsourced conclusion that the number belonged to Billy, for now anyway) - is that the upsetting call was to Julie at the New City number. This likelihood means that verifying Renner's source and information is important. For if both my reasoning and that source are solid, we have a complex and unlikely scenario surrounding that upsetting call.
In that context, two calls to action:
(1) James, we really need to know the source.
(2) Everyone else, we really need to consider if and where my reasoning goes off the rails. I don't claim all knowledge of the case. Am I missing something? Alternatively, do you have corroborating thoughts and facts? What do you think?
Finally, with the realizations above, some scenarios jump out of the sea of uncertainty, screaming out. For me, these align more simply with some other facts of the case than have previous conclusions and theories. In fact, it clarifies some things. But ... enough for today.