Stuck on 3: 35 down (11) Top of cloud had turned out to contain helium T???D???E?D and 36 down (6-5) Cautious - for example holding fund-raiser without one European premier S???T?-??R?T and 47down (6) Yank's prison clock it might be thought?E?S?E - if anyone can help I would be most grateful.
... but someone did post earlier today that it has happened before that it has been in the paper the following Saturday as the regular giant crossword.