Using a British Stamp when on holiday in Spain???

Have just listed for sale a postcard. Nothing special in itself but dose raise a question.
Spain and the Costa del Sol has for many years been the most popular destination for Brits looking for a cheap summer holiday.
But can you use a British Stamp to send a postcard home from Spain? The answer should be No but this card has a British Elizabeth II Stamp.

FUENGIROLA COSTA DEL SOL POSTCARD SPAIN BRITISH STAMP!

Fuengirola Sun Sea and Sea and Postcard from the Spanish Costa Del Sol.
Unusual Stamp question. Posted from Spain to the UK but using a British Stamp. Should not be possible!

http://www.my-little-auctions.com/a...OSTA-DEL-SOL-POSTCARD-SPAIN&auction_id=211929

 

It was he wording on the card. We are enjoying, not we enjoyed.
But Yes, quite possible posted on return home and would almost certainly have arrived faster if that was done.

 

Hmmmm! It's possible, I suppose that the card might have been mailed from Gibraltar, I don't know Gibraltar's proximity to Costa del Sol. Since there is not a full postmark (dial showing the town and date where cancel), it is also possible that the stamp may have been removed from another item and put on this card to make it appear somewhat unusual. Don't know, but it looks suspicious to me.

Don