You delivered the evidence earlier yourself. I've yet to witness in our area that you switch instantly from one type of State into another without a 24h cooldown period between.
My understanding is that lower-priority state to higher-priority state should never require a 1-day clear period between (which allows the transition up the priorities to potentially appear to clear some pending states by making them only active for milliseconds) ... higher-priority state to lower-priority state almost always does require a clear period but I wouldn't want to claim that as an absolute rule.
I don't believe this differs for Colonia (and I don't think the example I gave in this thread says anything about that one way or another)
Never has been witnessed here, yet from my memory I've seen a MF in two Systems having Wars at the same time in the Colonia region.
That could theoretically have happened in the bubble (and possibly even did but wasn't noticed, because the bubble is really big and mostly unmonitored) - it was a bug to do with expansion-by-invasion, which requires pretty specific conditions much harder to generate in most of the bubble than in Colonia.
They fixed that (or at least most of it) in 2.4.03: "
Implemented a fix to stop factions trying to invade during an expansion when they already had a conflict pending"
(At least, I think they fixed it. Adding that condition has made expansion-by-invasion much harder to get started in the first place, so no-one has managed it since 2.4, so it's hard to tell if the fix actually worked...)
Aside from that the other things you mentioned are also quite crucial to the difference.
Oh, the BGS in Colonia certainly works out quite differently to the BGS in Sol. No doubt about that.
However, so far as I can tell that's all to do with applying the same rules to very different initial conditions - which is fascinating, and what really got me in to BGS watching. Things like "what does murder do", "what does a Boom state do", etc. I would be extremely surprised to find any difference in.