That is fairly uncertain, SRS. Currently we have something called the Fixed Term Parliament Act, which both the main parties said they would scrap if they won the election. SO the question is, what is that replaced by? Apart from the war years, most Parliaments have been 5 years or less, but there have been six, seven and even longer if you go far enough back. You could even, conceptually, have no maximum at all, relying entirely on votes of no confidence, but that is exceeeding unlikely, even with this Government.

So I would guess that some time towards of the current five year period the Act will be changed to one specifying 'at most five years.'