Just for reference,
- Not sure if TK's default lounge is Plaza Premium FIRST. If so, there may not be a lot of people after all as you need to co-pay to get in even if you have access to Plaza Premium lounges in general with credit cards.
- The SQ lounge is the first lounge that business class passengers from Star Alliance flights go to, as it is closest to passport control and as it is an SQ lounge after all. Showers get very busy with 2 Lufthansa flights leaving at around the same time in addition.
- UA lounge remains open at that time (was there once for my flight on South African) - not crowded at all. I think they stay open for NH red eye flight to Tokyo. But even that night when I was there the shower was occupied at 2230pm.