Where would Quartararo go?
While riders will move to other manufacturers we have;
Ducati: Bagnaia, Martin, Bezzecchi, M Marquez and possibly Bastainini
KTM: Binder, Acosta
So the answer seems more likely to be Aprilia who has an aging rider and Honda that has the struggling injured Mir
I'm guessing that the big names in MotoGP won't shuffle until Ducati determine their factory team riders
The logical answer is Aprilia, but Aprilia aren't logical. As I have stated before, Aleix will likely continue IMO despite saying he won't renew his contract when he signed his last one. Despite Vinales being pretty average (11th in 22, 7th in 23 with 1 and 3 podiums respectively), I'm sure Aprilia will continue with him because no matter what he does, people still think the sun shines out of his arse.
Repsol Honda
Mir. I think his season is going to depend on how Marini does. This is Mir's chance to step up and lead the team but if he fails (or doesn't want to?) then I can see him fighting for a Pramac or similar ride.
Factory Ducari
Bastianini is the one under pressure, I don't see Bagnaia not getting a renewal, no matter how he does. Options for the second seat if Bastianini does get the boot are Martin, Marquez, maybe Bezzechi?
Aprilia
Probably continue with both riders, they don't seem interested in winning championships.
KTM
Binder is contracted, and I don;t see Miller being there for 25. So like most people, I believe Acosta will be the preferred choise unless he has a bas rookie season, with Marquez being an option.
Yamaha.
If Fabio leaves, maybe they throw Martin a big money contract to join?
Pramac/Gresini.
I believe these will be the most desirable seats for any factory refugees like Mir and Quartararo if they leave. I think Alex M is secure at Gresini, but Marc, Franco and Martin are question marks. The other variable is potentially Marc is happy enough at Gresini that he decides to stay and with all the extra sponsorship they will no doubt get with him being there means they can likely ask for factory spec bikes for 2025?
LCR.
Zarco is confirmed, I can;t see Honda allowed Ogura to keep saying no much longer so if he doesn't take the seat in 25 then I suspect he might be done.
Gasgas will likely keep Fernandez, and replace Acosta with Miller if the former goes to factory. I'd hope they'd get another young talent but we will see. At that point Fernandez will be in his 3rd season so shouldn't need an experienced team mate.
The rest I think won't change much but if it does, won't really affect the pecking order.
Miller, Martin, Morbidelli contracts up, end of '24. None of them have Fabio's consistency, nor have any won a WC.
At the time of writing, everyone bar Binder, Zarco and Marini have contracts up.