Shit, sorry to hear that, sounds like they have more on atm than they can manage.
You should be able to take the work they have done so far to a different contractor though?
Looking at their offer, it doesn't look like the heavy construction side of things is integrated in the practice. They might be have a good relationship with builders for the heavier stuff, but my guess is this is put under strain with supply issues and recent material costs increases.
Shit, sorry to hear that, sounds like they have more on atm than they can manage.
You should be able to take the work they have done so far to a different contractor though?