Yes, but it’s difficult because (as I understand it) the French refresh cycle is out of sync with the US/UK refresh cycle.

And even if the UK decided it was ok with spending extra money early, or going without nukes for a transitional period, the French option would be more expensive (not the same economies of scale).

Plus, the UK still wouldn’t have the expertise to maintain the things, so now it would be vulnerable to the French reneging instead.