The challenge is to give Britain with a POD of no earlier than 1700 either a colony or an actual constituent part of the UK on the European mainland and Gibraltar does not count
Well, if we go for the obvious 'Victoria born a boy' PoD, extending the PU until, in all likelyhood, after the German Unification, the Nobles in Hannover may decide that the best way to preserve their power and independence is an act of union with Britain, keeping institutions etc. like the Scots did.