thanks so much for the explanation, sw. That all makes sense now. Both LL and TH were trying to reach him multiple days starting Sunday so was not a memorable call on Sunday only to associate with SK disappearing that day.
I spent some time looking at ping map you and laytonian put together. Great work. With the caveat that I'm not super knowledgeable about how the cell phone / tower communications work, here are my thoughts on it.
My first thought is how close Steven was all morning Sunday to where he parked his car. Although we see different towers involved with the pings, they are in two groups; one general area where he parked his car and one general area up from there to the interstate at Whitney Ranch.
When cell towers overlap, they all recieve signals from the cell phone. I do not know all the logic involved in determining what tower will handle a call. I know timing of transmissions can be made and that this is used in one pseudo-GPS technique called triangulation, approximating location from time it takes to transmit a signal to multiple towers. But that isn't the point here.
Since the towers in the two areas are close to each other, it's not a given to me that he's moving, for example between the ower handling the first call taken before 8am and two hours later tower where second call taken. They are both within transmission distance of where he parked his car AFAIK. It is not a given to me that both calls would necessarily handled by same tower in an overlapping situation. If engineers say that is not the case, then strike this but my thought is that SK could have been where he was Sunday morning, indeed even late Saturday night after leaving his small apartment in St. George at 9:28pm. (Were the 9:02pm and 9:32pm calls identified?)
The same thing is true of the group of towers handling the 4:36pm and 7pm calls and then 7am next morning. Having said that, it's a bit of a hike but seems to be just about hiking speed to get from where his car was parked at noon to tower where ping is recorded at 4:36, then on northward to next tower where ping is recorded at 7pm, then up to interstate where ping is recorded at 7 in morning when voice mail is checked.
It looks for all the world like someone hiking out of Henderson and then maybe thumbing a ride on the interstate at a truck stop or something. Or done by someone to make it look that way.
I say hiking in the sense that it's a good walk, but Henderson is cited as one of the most walkable cities in the country according to Wikipedia. Of course that ends when you get to interstate and getting somewhere across the desert.
But although nicely headed north in terms of tower communications, they are relatively close together and could be handling calls at one location, a location that SK could still be at dead or alive to this day. Again, engineers may be able to tell us that communications among overlapping towers would not work that way, but if you have three towers able to hear the cell phone, I don't think they mediate to determine who is closest. I think one of them grabs it. And could be different ones different times. Hopefully a knowledgeable person will be able to clarify how that works (or I end up googling that question and get an answer which I haven't tried yet, just finished looking at map.)
I am most intrigued by SK being in general area of SCA all morning from early on. I have thought that where he was would be significant and wondered why no trace of him existed from 9:28pm previous evening. Driving around other nearby neighborhoods doing same thing he was doing when he walked away from his car at noon? Possible, I guess, if extremely puzzling and very difficult to see how no memorable encounter with anyone was made if out and about walking neighborhoods.
But as pointed out, he looks like he knew where he was going, where to park, and where he was heading, and while he may have scouted it out that morning, I would say he wasn't necessarily that far away all morning.
Also looking at ping map, it seems more probable to me what laytonian has suggested, that previous morning ping in Overton was also a trip to Vegas / Henderson, for same purpose. It would be a much shorter trip, maybe 9am to 3pm at most in Henderson, but could be where he made contact in person to come back next day at noon.
This is a classic dilemma, where strong arguments can be made that Steven hiked away from that car north to the interstate and sites unknown, or set up as a victim to disappear. Something may become known to tip the scale one way or the other, but right now it's a complete tossup.
rd