OK how do i explain this in a way people that are not me understand…
to my understanding jobs will have levels and exp at some point, and as much as i don’t see your carpenter suddenly becoming a farmer just because u don’t need a carpenter right now, i also get that if your farmer died to a raid u might need someone to look after the crops.
its my opinion that you should be able to demote a person but they would lose all exp in that field, i feel that a skill system could still lead to a few people in your town becoming quick swapers who you constantly change the job of so they gain xp in all of these jobs, ie what if u rotated the sword around your people so they all became good at combat and just had spare swords in storage for when u got attacked. suddenly your whole village are knights, but they can do there normal jobs too?
also to put you at ease and i might be wrong on this but its my interpretation that one does not “upgrade” from a farmer to a brewer, but merely you require a farmer to be able to make the tool for a brewer, you still would need a farmer to tend the crops, so its not that it don’t matter which job you take but rather do u want your town to have lots of beer or be flower hugging druids or even both if you want too.
on that note though id say that some skills from a farmer would help a brewer do his job, so i believe that you should have the option to upgrade from a job to a better one, with only losing say 50% xp meaning that if one had a legendary farmer he would become a great brewer as he knows what a good grain looks like and can pick the best for his brew ^_^.
this then gives the player a further choice of do u make that worker who only knows how to drink beer the brewer and only be able to make the lowest grade of beer, or do u lose your awesome farmer but get a better brewer?
this could work with many jobs for instance footman would know a bit about combat so any other combat role would be and upgrade, but using a new weapon would take some getting used too, so he would take the xp loss, but if he was to stay a foot man and get better gear like a shiny new sword and some armor he could be come a good footman too. but having a foot man could still be a requirement to making a worker say a great weapon user, as the blacksmith would need help as to where to make the pointy end?
anyway that’s probably a wall of text >.<