Obviously the turning point is the proposal to federalise, we'd need the four factions to have compelling reasons to not stand apart, three of the factions were part of the initial fedsralisation proposal, it was hoped that Albionoria would have come later. Let's look at Quebec as am example, you'd probably have to look much further back than actual federalisation, perhaps a century before and when the Bourbons were dangerously close go having to cede New France to the British. Let's say they did, then you avoid Quebec becoming the sanctuary of the deposed Bourbon monarchy when Bonaparte rises, but obviously the Bourbons made a hash of the matter and got jettisoned pretty sharply.
I mean, when Bonaparte fell, it's not like they didn't get back to France to reclaim the crown anyways. Quebec under British control wouldn't have experienced it's own monarchy, nor the Quebec Rebellion of 1830, and would have got largely used to being it's own entity and would never have wanted to cede more control than was absolutely required at a minimum away from the Presidente Quebecois in Montreal.
I mean, it's a long and convoluted process, but you get my drift.
