Tory members want her to go, which must be about the last lever to fall. If you scroll down the link you can see they want MPs to decide the successor, though they actually want johnson back in.
Anyway, I'd actually put good money on this being the way it goes - 1922 decides these are exceptional circumstances and allows MPs to decide a unity candidate. Sunak and possibly Mordor favourites, but Cunt might feature. Brief period of feverish lobbying and jockeying for position, followed by1 candidate emerging. Unfortunately, no Red Wedding.
Boris Johnson is the most popular successor
yougov.co.uk