After the latest update and change from cowriters to writelier it seems I have been writing posts from the future. For some reason the posts show the next day as their publication date. I haven't checked whether this is only an issue with posts written later in the evening (which would kind of make sense) or all posts regardless the actual time of writing.
Luckily it hasn't affected my streak, even though there should be a jump somewhere around the switch over date. Only thing bothering me is the notification that I haven't yet written today persisting on the page despite the fact that I just posted and there should be the post from the day before that should be posted under today's date. But neither of those seems to count for the timer.
Writing any code dealing with datetime is one of the most challenging tasks in programming. Despite it being an integral part of so many applications it's still really easy to get wrong. There is just so many odd border cases that need to be considered, all the different timezones that need to be accounted for and so on.
I almost think that it would probably be easier to switch over to global time and date system that would solve all those issues than get one software handling all the possible datetime issues correctly.