I think it highly unlikely that 'windfalls' would not be included, as far as I am aware it's a standard clause that's inserted in all proposals.
I'm sure the experts will correct me if I'm wrong [:D][:D]
IVA COMPLETED ON THE 17th MARCH, FINAL I&E COMPLETED 26th APRIL, COMPLETION CERTIFICATE ARRIVED 2nd AUGUST
If there is nothing expressly mentioned in the proposal it is almost certainly covered by the standard terms and conditions whether protocol or R3. I very much doubt if you would be exempt from the windfall provision.