I live in Europe.
I have 2 full install on my PC: Lubuntu minimal 64 bit rel. 17.04RC and Debian9.0RC 64 bit.
we did have last month our summer time changing.
Ubuntu did adapt itself the time correctly.
Debian not. The time is wrong since this date and stay wrong and will probably stay wrong all the summer time until the next time changing for the winter
I will check the data concerning time in both, Ubuntu and Debian.
Which files in (probably) /etc oder /usr/share are concerned?