The question is simple when does a creature exiled by Lukka, Coppercoat Outcast's first ability lose "You may cast this card from exile as long as you control a Lukka planeswalker" ability? Is it when it is cast from exile? Is it when it gets put back in exile? Or is it when the game is over? On the off chance it is the last one then one could recycle a creature like "Farfinder" if it was one of the creatures marked by Lukka's first ability, right?
The thing tripping me up is that normally cards that give abilities like this state something like "until end of turn" or "until the beginning of your next upkeep" but this one doesn't which is throwing me off and making me feel like it must be something or that it must be affected by a rule I am that is along the lines of one that states something along the lines of "...when a card changes zones it is treat as a new copy of the same card...".