Here's a feature that is decidedly experimental, in that I'm not 100% positive I've got it right. I'm not even 75% positive. But let's give it a shot.
I've just pushed a change to the server that will automatically adjust post times (see the image below) for your specific time zone and locale. If your computer is set up reasonably properly (and I suspect that most people running modern computers are in this category) then you shouldn't have to do anything.
In theory, this will adjust for Daylight Savings Time, if it is observed in your locale. Again, it's based on how your computer is set up.
The time zone offset and date / time format fields in your profile are now obsolete, and (if this feature works out) will be removed in the near future. But it's quite possible I've overlooked some detail, or someone will claim that they need their post times to be relative to Botswana time, or something.
In any case, take a look at the post times in an actual topic and see if it seems legit for your location.