UBB.threads PHP Forum Software Community Forums UBB.classic [Archived] UBB.classic Bugs [NOTABUG]6.6.1 Adjusting Date & Time: Default Time Offset (Hours) doesn't do anything

No, it is only the default for new users. If a user has logged in since the upgrade to 6.5 or so, then they'll have either the board default offset or their profile offset in a cookie. Adjusting the defualt offset later on will not impact users that are logged in, but will impact users that aren't.