Apologies to resurrect an old thread but figure this might be the right place to post this so others can find in the future....

I'm trying to take advantage of the much cheaper ex-CGK vs ex-SIN prices. Does anyone know what the airside transfer situation is like if I fly in on SQ (also to T3) and want to transfer to QR? Ideally I don't want to pay (and queue) for the visa on arrival for a transfer. Can assume hand baggage only.

I've heard there are transfer desks. And that as long as you have a boarding pass you can go to departure levels before clearing immigration. Does anyone know if these transfer desks have a QR rep at them? Has anyone done this? I'm concerned about the (50/50 at the moment ime around Asia) case where I won't be able to get a mobile boarding pass.