My ruling is likely to lean on consultation with at least Vilage, since he's the only one currently active of the oldest old guard if I have any issues. But I'll have to lean on the consensus made in this thread: that the UK probably would have retained its Atlantic ocean territories and Americas possessions.

Though also given how the British Empire functions, Australia and New Zealand as much as Canada are probably still in some lose association with the British Empire. So at worse many of the smaller British possessions in the Pacific could be argued to have been shifted over to Australian administration in something akin to CK2 title management.