A large portion of the people who were in the Labour Party will not be in it shortly.

Some will just leave and drift out of direct participation in political parties.

Some may join the Lib-Dems.

Some MPs may resign the whip and form a new group in parliament?—one which may even mutate into a political party with an infrastructure of its own. If this happens, it’s possible that it would reach some kind of accommodation with the Lib-Dems. This would be an SDP MkII without the fanfare. Or the big hitters.

Who knows?
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