According to the July 7th update from Heard County Sheriff's Office investigator Dan Boswell ...
Update from Investigator Dan Boswell on July 7th, 2020
The last location where her cell phone was communicating with a tower was in Heard County South/Southeast of the Ephesus Cell Tower, approximately 4.22 miles.
The cell tower mentioned is going to be this one (red pin).
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And 4.22 miles S/SE of there would be somewhere near or on GA 100 near the intersection with Thaxton RD.
That last contact was at (or around) 4:40 AM ET. She was last seen in Jackson's Gap, AL at 12:52 AM CT (1:52 AM ET). So that is nearly 3 hours between those times.
It seems strange to me that she traveled that way to get home since the interstate would have been faster - the last address I have for her is in Grantville. The person I believe to be her ex-husband has an address in the Newell, AL area about 17 minutes from Ephesus, GA. Was he also at that 4th of July gathering? Did she go up there for some reason?