It's not the passage of time that's weird. It's that none of them who write for Star Wars really care about continuity. I'd say even George Lucas doesn't care about continuity. All that matters to any of them is "Does it make money? Does it sound good?"
Everyone who writes for Star Wars wants to put their own spin on things, wants to make their mark, and they'll change anything and everything as they see fit/can get away with. TOR is no exception to this rule.
I think it's also hard in such a big universe to never have anything that contradicts something else.