Same issue here... talked to Verizon and Apple
In NC with Verizon. Same issue started with me today.
Time switched to some funky time, and the date was set back to August 27th. I believe there is some issue when switching between Wifi, 3G and LTE networks. I also live in one of those areas where I am frequently going from 3G to LTE with Verizon.
I called Verizon, they asked me to do a hard reset, then transferred me to level 2 Verizon support which then transferred me to Apple Support. Both Verizon and level 1 person at Apple, basically said "I've never heard of this before, but it seems to be fixed now". Finally, I told the Apple support that I wanted to talk to someone who might actually want to find/fix the problem without apologizing for it. They sent me to a level 2 guy who gave me a case number, his email, phone number and asked me to log and track the issue and report back. It may not do any good, but I feel important when I have a "case number"... especially with Apple