Well, I haven't seen a different feature and I lost one of the advisor slots that gave quests. Sure looks like the cause was the cauldron. The "replacement" only deals with the cauldron.
That's temporary. You would have lost the quests in a couple of weeks even if the cauldron was never invented.
Daily and weekly tasks called "seasons" are replacing the quests, the devs appear to have used this opportunity to first get rid of the old quests and introduce the cauldron at the same time.
Eventually, the cauldron line will finish though, and those quests will be replaced by seasons.