Something new that occured to me few days ago. A BPG claim was discussed and initially denied by Customer Service L1 (typical as they don't know how to approve their own guarantees). It so happened that the claim was approved after the end of the stay. Accor unilaterally took the decision to convert the difference they owed in points and sent that to me. I'm still trying to get that fixed.
Usually, properties issue refunds directly to your credit card.