Great advice actually. For those with airline status there are also some lovely lounges at Changi which might be good for a few glasses of wine on the way back!
Glad you made it! I'm sure there will be an anonymous doom post soon about someone being asked to rustle up a competent Pad Thai on the spot by a suspicious immigration officer 😂
I found the UK embassy efficient and sensible - if you're in the UK I'd consider applying there rather than in SE Asia. Workcation from home country seems to be the 'gold standard' for DTVs.