Indeed, the tavern job changes to a different one (with better lust reduction) between upgrade two and three. If you put them there permanently, they can even get lost. Will be fixed in the next update.
I purposefully cask of Amontillado'd a few recruits like that... y'know ...for profit.
Just so you know they will still earn 10 gold each day regardless of other upgrades to the tavern which was kinda disappointing as I was hoping to be able to use this method to get a full 8 guests in the tavern.
