13.1 of the Declaration of Condominium, at least on the SSR one does simply day that DVD must be given at least 30 days notice before closing. It says that DVD MUST give notice in writing before the proposed closing date if it wishes to exercise ROFR. It also says the owner can sell if no notice is received before the closing date.
So the notice period is entirely within the sellers control. If it gives DVD the 30 days notice of the closing date and DVD doesn't reply in that time, then DVD only gets 30 days and the seller can close, seller does not have to wait for any notice of waiver of ROFR.
If seller gives DVD 50 days, DVD has 50 days and so on.