Originally Posted by SilverChris

I'd say your chances are vitually zero. It'll be tough to find an SQ agent who's willing to touch a non-SQ issued award ticket in the absence of IRROPS.

I've tried my luck several times to be put on the next day's SIN-KUL flight on a *A award ticket but no to avail, both at the transfer counters and landside check-in. They'll just tell you to contact the airline issued your ticket.