Hello and thanks for using Just Answer.
I am Al and am happy to assist you with your enquiry.
As I am local to Walsall, I am aware that when Walsall MBC sold on their housing stock to Walsall Housing Trust/Walsall Housing Group, this clawback provision relates only to circumstances where WHT/WHG obtain planning permission for a new development- ie a new housing estate/redevelopment of land. Hence, it does not apply to any renovation or extension of any existing property.
I hope this assists and answers your question.