Mark
I would be getting onto Virtue and asking them how they managed to come to 184.5A for a 3/4? bed domestic dwelling. I wouldn’t get involved just incase
I’ll write you something up to email but, my guess is they are clowns for getting the basics wrong or as I imagine mixed up figures with another job.
Equally I don’t like the fact they have said it is you a layman so to speak who has done the calculations as far as the DNO are aware. This IMO needs reporting to motability in writing at some point!