I certainly had an interesting experience with SQ yesterday - my oldest (20) is flying back from AMS-SIN on SQ323 tomorrow and they cancelled the 9:30ish service SIN-SYD about 20 minutes after I confirmed the original flights online. What followed was the better part of 5 hours on-hold with SQ trying to sort it out, but we managed to get them booked on SQ221, which looks like one of the few (or only) SIN-SYD each day. The first agent I spoke to was going to sort it all out, put me on hold and never came back! Quite a trying day, although I wasn't really frustrated at SQ, as I've only found their customer service to be exceptional in the past --- it's just complete bedlam right now.
(I've also just had about 3 J flights cancelled on SQ in mid-April SYD-AMS return, which is expected)