Re: Why do only SOME of my text messages are dated 8+ hours wrong
I'm guessing you're in the Pacific time zone?
It happens when the phone is roaming and you receive a message. It can't get the correct network time reference, so it defaults to UTC (Coordinated Universal Time) because that's the universal world time which all time zones reference (and the time that SMS uses).
It's not the app specifically, though there may be other apps that will reference the phones internal time when time stamping messages, but I don't know of any.