18+ student oyster card stolen, now what to do?

My wallet was stolen abroad which had my 18+ oyster card in it, I don't think I had much money on it anyway but I just wanted to ask, is there any point in reporting it stolen to TFL and getting a new card? Don't we have to get a new 18+ oyster card for the next academic year this september, but if I do wait till september do I have to report my old one stolen to them then?