Turns out flights from SIN-LHR were also subbed with 777ERs on both days, it appears SQ made no attempt at contacting passengers to notify them, I guess you need to keep an eye on their website for such changes.

Anyway, the notice I was presented with stated that they needed to "re-accommodate 6 pax originally booked in business class" - I don't actually know what that ended up meaning for the said passengers. There were a couple of passengers on board originally booked on Suites who were downgraded to F too.

The 777ER biz seat is noticeably different to the 380 in terms of comfort and having been assigned the very last seats in the cabin, we had little choice for both meals and none for desserts as all the better stuff had already been taken. I must say it was one of the poorer experiences we have had with SQ and there certainly was none of the "SQ will move mountains to appease its TPPS pax" experiences frequently eluded to here. I guess we should just be grateful that we were 'allowed' to depart and arrive at the times we were originally scheduled to!