Yeah, it was largely Patrick looked better in red. Likewise under the new system Data was supposed to be in red, but it clashed with his makeup so they put him in gold.
It’s acknowledged in universe but they’ve never said why. Just “back then it was the other way around”.
No doubt fans back then were angry at the unexplained canon change.
They’ve never been consistent in how stardates work and only really just try to make sure they run in a chronological (if inconsistent) order. I’d wave off exact translations of stardates for this reason.
But also allow for human error. I know an event which miscalculated how long they’ve been running based on failing to understand how anniversaries work, and thus have put out a whole lot of material stating they started running a year earlier than they actually did. They could have checked the archives, but didn’t.
Given how Trek is about the human condition, I think character’s messing up basic facts is as good a canon fix as “The Doctor lies” is for Dr Who.