It may depend on the service used. Different companies maintain different records. Also what towers they either leased or owned, at that time, can factor in. How the antennas were configured.
There are a lot of variables.
Because LE appears to have gotten phone records somewhat quickly, after JK went missing, these records probably do contain a great deal of info.
Even predictable people can do unpredictable things. More so than the JK's phone pinging or not pinging after 10:40 PM, I wonder about the mace left on the kitchen counter.
She always carried mace, yet it wasn't taken with her that day. Was there just not enough room in her purse, or was she not on her game that morning? Distracted? Or was there a knock on her door early that morning, that because it was morning, she might not have been afraid to answer?
I don't know if the mace being left behind, points more to a night abduction, but it's one of the first things that her mother reports was concerning to her.