I found the video where cujenn81 drove to LB's, following the route Heather's phone took. Here's a link to that post, which includes a link to the video:
http://www.websleuths.com/forums/showthread.php?311195-Sidney-Moorer-on-trial-for-the-kidnapping-of-Heather-Elvis-***MISTRIAL-declared***-2&p=12676497#post12676497
You can click on the following images to enlarge them.
Here's a screenshot of a post where we know that per (someone's?) testimony, her phone turned around at Seaside Grove Apartments and headed back to LB's.
View attachment 122553
Here's a map that shows Heather's apartment (yellow star), Seaside Grove Apts (yellow car), and Longbeard's (red marker).
View attachment 122554
Sorry it's taken so long to respond about any of this. I found these things in the Kidnapping Mistrial (#2) thread. I have to run out, but later I'll look through thread #1 to try and find more about that testimony. Maybe it will shed some light on how they know where she turned around.