Today, 30th November 2016, is the last day to transfer your Avios out of your Diamond Club accounts if you still have an active one. You can do this via the Combine My Avios tool on British Airways.
Also ending is the 10% British Airways discount given to holders of the Diamond Club credit card. So if you want to do a final bit of shopping for flights then make sure you do so before midnight tonight UK time.
Goodbye Diamond Club, we'll miss you. You were one of the best programmes in the whole air miles hobby! :'(