Say you do trial of zeal first battle (1.1) with your kiora. You make a deck for the objects and play the event. When toz comes around the next weekend and you open that node (1.1) it pops up a box saying “you used kiora last time for this fight do you want to use the same deck?” and if you hit no it just takes you to the normal pw selection. For events that lock the pw to the node, have the popup indicate that this is the only chance to reuse the old deck w/o building from scratch.
Side note: some kind of warning on events that lock pw to nodes would be nice.