Thanks Garin for that. I take my Credit Card to Cuba solely as a back up and would only use it in an emergency, and as I don't possess a card from either of these two institutions it would not affect me anyway.
I know a lot of Brits, in the past, have been confused about which Credit cards will be accepted in Cuba and you are bang on in saying that at present any card issued by HSBC will not be accepted, so that if this take over does take place it will be the case of another credit card biting the dust as far as Cuban use is concerned anyway.