If I am not mistaken max days to sit is still 21? so if the system was changed to where sitting is linked to the province and not the user that would fix abuse for the most part. Until then maybe we should just hope people won't abuse it. Yes, I know some will, and we all know who too. But for the vast majority it's a great change that will make playing a lot easier for example if you planned your return time and then your boss tells you you are working overtime, or if your kingdom is planning a wave exactly when you are in surgery etc
And maybe the devs can keep a close eye out for those that like to abuse game mechanics ;) cause they know who that is too and hand out penalties more freely.