I think that's fine. There's seems to be a rudimentary quest log, and at the literal end of current content, a one-time message isn't too bad either. Those are appropriate use of "hey, heads up, this is wip ..."
But it shouldn't be in the middle of dialogues, with explanations of how things might be different in the future (I think the landlady character has that), or like the inventory in the minigame (just disable it).
Obviously just my opinion and tbh also the smallest of issues. Though, yeah, probably good to get a good flow on how to mark end-of-content stuff at the beginning in a simple way still.