Today was the first time that I have watched the news video with the car at the crime scene and then possibly after it was towed. The first thing that struck me was that there appears to be damage to the driver's side front wheel/tire and hubcap. the fact that she put up a good fight and the phone was in close proximity to her fingertips as well as what sounds like a frenzied attack, makes me wonder if their was some kind of road rage incident after some minor collision.
The other thing that stands out is the nearly one hour time frame from the Time Warner CCTV and the phone message or attempted call to a friend/acquaintance family member, whoever. Then there is almost another hour and a half before the passerby calls 911. Where did she go between 2:30 and 4:00 PM?
Before heading to the Time Warner location, did she fill up her tank, at the gas station, or just buy some gas or just convenience item/items? This is important because the car was found running and at least 2 1/2 hours passed from the time she left Time Warner....only five minutes away (1.6 miles.) The amount of gas purchased and what was left left in the car could indicate how much was used.
IMO, either she met up with an acquaintance or went to meet someone and/or did more errands or she was attacked in some sort of a road rage incident. The road rage incident makes the most sense to me. Let's say an incident occurs and she tries to evade an angry driver, she ends up down there, the other driver forces her off the road, comes at her car enraged, she grabs her phone to call for help and she tries to get away but is grabbed and a physical altercation ensues. If it were a bump and abduct situation, IMO, the killer would have had a better location planned and Amber wouldn't have been left there with her engine running and the phone right near her hand.