A rather long and complicated story here, but basically I have acquired a site with extant planning permission for a house that was never built (but where the foundations were started and so it is considered materially commenced). Because the planning permission predates CIL, if we build it exactly as per the plans, we pay no CIL. The internal layout proposed is dreadful and i'd like to make some changes but if I submit a material amendment request then CIL kicks in for the whole build and it would be nearly £100k, so I definitely don't want to do that. I'm struggling to find clarification on whether the planners care about the internal layout or not and whether I can make internal changes without permission for a house that has not been built/signed off yet? Can anyone tell me please? Do I have to build it as planned then make changes afterwards instead? Thanks