So, confirmed I have paid for seats that haven’t been assigned, and allegedly can’t be assigned. They’ve offered 2A and 2C instead. Albeit, still waiting for the call and now they’re not accepting new calls.
If things get more complex, just ask for a refund. There are good reasons for paying for seating on BA generally, but not in Club Europe due to way that Theoretical Seating (see Dashboard thread) and the curtain operates between CE and ET. It would be most unusual if you could not sit together and get the particular aisle/window combination that you prefer. All you may be getting is row 2 as opposed to row 4, and row 1 may well be available at OLCI anyway. It would certainly be easier to do at OLCI, and cheaper, than multiple phone calls for a short sector flight.
Alternatively do nothing: if OLCI doesn't give you the paid for seats, you can use the webform for a refund anyway.