We are transiting through Changi this December and our flight arrives at about 9pm but our connecting flight to Penang doest leave until 10am the next day. Can we use these lounges on arrival and stay until closing time? We are Emerald One World flying business?

Don't get the bloody mary on Qantas. It's a premix and flavour is awful and  can't be adjusted to taste.

Totally agree. Whilst better than economy, anything over 4 hours in this seat is going to be mighty uncomfortable. The A220 may have the legs to travel to SE Asia, but I'll choose another carrier with lie flat any day of the week if they start using it for international flights.

Business class very uninspiring and looks just as cramped as the 737. . Will the reduced number of business class seats mean a price hike for these seats or less availability for Rewards seats? I've just received a notification from QF that my flight to Melbourne will now be in the new A220. ...

Unlikely that this will ever happen.  Without this sweetener, I,m of the opinion that a lot of premium travellers will spend their $$ on airlines with both better hard and soft products.