Unless you're having some unique materials or specialist building methods then you wouldn't need working drawings.......unless your builder doesn't know what he's doing either!
Sounds like, though, you just have planning permission drawings and not building regulation drawings. Like has been said, if there's a doubt the you might not obtain planning then you wouldn't provide building regs drawings as its a waste of money. If your architect is pretty confident that your plans will pass then he could provide one set of detailed building regs plans and submit them for both.
But your builder still needs a set of building regulations plans and local councils pretty much expect a full plans application these days anyway.
Sounds like, though, you just have planning permission drawings and not building regulation drawings. Like has been said, if there's a doubt the you might not obtain planning then you wouldn't provide building regs drawings as its a waste of money. If your architect is pretty confident that your plans will pass then he could provide one set of detailed building regs plans and submit them for both.
But your builder still needs a set of building regulations plans and local councils pretty much expect a full plans application these days anyway.