AFAIK, changing/cancelling PB stays can be a mess, and that's why we used to make single day bookings because we don't have to risk loosing the whole thing if our plans changed. With the new rules this is no longer doable anymore.
We stayed at a PB property last week and we booked 2 rooms (1 member each), and both rooms had bad smell and we asked to change room. FD said that they are all sold out due to a dog show, but we really don't want to stay in rooms that smells of a locker room. After a while she came up with a solution that we all stayed in a kids suite instead of 2 rooms (she said it's a room that they never get to sell). She agreed to refund the points for 1 of the rooms.
It has been more than a week and no points yet - I wrote to the hotel and they said they will do it. That's the problem with IHG - if the hotel would work with you, things will turn out fine, but if they refuse then don't count on the corporate to do anything to help you.