I'm sure this has been covered here but I can't seem to find it.
We have rules for upgrading magic items but do the rules cover removing magical properties as well? If a player has invested in an item with the keen property, can they remove keen later (say, once they get access to Improved Critical)? Or do they need to sell the item at half value and start fresh?
And while this is intended to be a general rules question, if anyone ALSO knows whether this would be allowed in PFS please comment on that as well.