RichL

Last but one time I stayed at the Atlantis, I was in a similar situation to you, waiting for a new card. So I did exactly what other people here have suggested and printed off a paper copy of my membership. The printout is exactly the same size as a real card, so you just cut it out.
Receptionist didn't bat an eyelid............
Make sure you keep on handing in the card every time you spend in any of the restaurants or bars as you will get 15% discount. You need to show the card every time you ask for the bill though to ensure you receive discount. Expecting it to appear at the time you check out of the hotel as you hand the card in initially at reception is likely to result in disappointment!