Dual pax booking on a connecting flight to AKL then SIN. The initial regional leg got cancelled and we were off-loaded from the AKL to SIN flight (operated by SQ in J).

I immediately called Air NZ after receiving the notification and asked to not be off-loaded as we could make our own way to AKL, unfortunately they said there was no longer any availability in J and sure enough there was only Z1 displaying on Expert Flyer.

Despite this, I could still see the booking on the SQ website and following the flight's departure we got an email telling us that we have missed our flight and to call them to arrange alternatives.

Does anybody know where our seats could have gone to? I thought maybe pending SQ upgrades got automatically cleared... We have also been rebooked onto a budget non star alliance airline, is there any compensation for this (as we'd have no lounge access/completely different product/no SP/APD earnings etc.)