Evidently the "Adjust remote timestamp with DST (Windows" didn't take when I tried it before. It's working correctly now. :D
Before posting, please read how to report bug or request support effectively.
Bug reports without an attached log file are usually useless.
I should mention however that it did have the problems with files created before DST started
That's wrong. Server adjusts DST is for Windows servers. You should use Server works in UTC time.
If I have understood correctly what you want, I first Load the stored session, and then I click on Environment. Here I see Daylight Savings Time -> Server adjusts DST checked.
Thanks. What is your "daylight saving time" settings on Environment tab of login dialog? also what version of WinSCP are you using?
If you login using the same settings in GUI, what timestamps do you see in local and remote panels?