If he's incapacitated before the convention, Jill Biden or his sister will run in his place.
It's not too late to start thinking about the Demonrat pick for VP. That's who the deep state really wants as POTUS.
I think that the establishment Dems certainly are looking hard at old Joe’s VP choice. Worst case for them is that Trump wins in November. They think that’s pretty likely, so they don’t want to put up one of the younger candidates like Butigeg (or however the heck you spell it). Biden’s the sacrificial lamb in that case. Maybe though he pulls it off. He’s 77 now and 81 by term’s end so it would be no surprise if he doesn’t live to see 2024. Even if he does, would anyone even question a 25th Amendment proceeding claiming he’s mentally incapacitated? Old Joe’s VP almost certainly would end up POTUS and would be the Dems candidate in 2024.
If he wins, I’ve been saying Feb 2, 2021. If he loses, (which he will), it will be closer to November 15th or so.