[sky13]

Hmmm, this is a bit tricky. Honestly for HK/Singapore my airlines of choice would be either Cathay Pacific (HK based) or Singapore Airlines (Singapore based), but I don't think either one flies to Edinburgh (both fly to London though and if I don't remember wrongly Singapore Airlines also flies to Manchester).

I guess there are a few choices that come to mind:

1) Book with a carrier that flies to Edinburgh - this includes Qatar (which is fantastic for long haul, I flew long haul with them last year and the year before and was very impressed). You could potentially do this as an open jaw - so Edinburgh-(intermediate airport)-HKG, with return being SIN-(intermediate airport)-Edinburgh. Then book the HKG-SIN flight separately (plenty of airlines fly this route including budget airlines).

2) Fly from another UK airport with either Cathay Pacific or Singapore Airlines. The advantage of flying with either of these airlines is that you can usually get a free stopover in the home city. So you could potentially fly Cathay Pacific on a UK-HKG, then HKG-SIN, then SIN-HKG-UK route, or Singapore Airlines on a UK-SIN-HKG, HKG-SIN, then SIN-UK route.

3) Do codeshare flights - so multiple airlines on a single ticket. Maybe do a search on Kayak and see if anything comes up?