Oh, M wouldn’t have to die. This version was introduced as a bit of a Whitehall career horse, supposedly even so familiar to ordinary troopers that they immediately jump at attention when he growls something about ‘00-section’ (which we may assume is something so well known not even the tabloids bother to cover any more…).
So this M gets a promotion and this Bond gets to meet the Queen again. It’s the logical conclusion to a career we’ve seen from start to finish. They could even shoehorn the Royal Navy in by making Bond (rear) admiral.
Yes, it blows everything. But I bet Fleming wouldn’t have complained. What I mean is, if we’re bold we can be really bold, not just a teeny-tiny bit of b-b-bold-and-let’s-finish-before-we’re-caught kind of. Nobody would count on such an outcome.