British Airways has provided the following statement today:
Our IT systems are back up and running and our operation continues to run as planned today with a full flight schedule at Heathrow and Gatwick.
We are extremely sorry for the frustration and inconvenience customers experienced over the Bank Holiday weekend and thank them for their patience and understanding.
We are continuing to work to get delayed bags to customers as quickly as possible. Information on how to report and track delayed bags can be found on ba.com.