Again I am saying 'months' here, and once more looking at Jeremy Corbyn's career (such as it will turn out to be) as Labour party leader.
It is now two months since he became the leader of Her Majesty's Loyal Opposition party, and with a struggle has now even become a member of the Privy Council – which he is required to be in his position, but avoided once (on a flimsy pretext) and apparently didn't conform fully to the accepted protocols on the second occasion – but got away with that.
Rather than present a catalogue of causes of his upcoming (and necessary) departure from his new position, I think this by Iain Martin covers most of the bases, and is thus useful reading.
In practice, there is no reason to believe that Mr Corbyn will either step down from his party leadership position any time soon, or be successfully ousted. It could drag on for years, helped by the Labour party's own rules and procedures. Nevertheless, it should be noted that this was the month when his position became permanently untenable and he was now clearly an irreversible detraction from Labour's electoral and broader public standing.
The longer he remains, the more the public will learn of the true nature of Labour, usually hidden beneath a veneer of apparent respectability, so I am hoping it really does take years to oust him.