I wonder if the software update may have either become stuck, or had a poor signal and kept on trying to update until the battery wore down. I could see that happening.I know, right? The day before that night my Escape turned into a 2-ton paperweight, I'd done plenty of driving, both on arterials and the freeway. It had sat for barely more than a day.
I'm still inclined to think that the SYNC software update is to blame, even if the dealer's service department are clueless. That's the only thing that's recently changed. For now I'll be keeping an eye on it, and hope the next update solves the problem (assuming it wasn't just a one-off thing).