It’s conceivable that it could, and so it makes some sense to prepare. Even assuming it’s over by then though, it still makes some sense to prop up Ukraine both militarily and economically for some time after, because seeing as the war has been mostly fought on their territory, it will be a long struggle to rebuild, during which time it may be difficult for them to afford to replace military stockpiles on their own as they’ll need everything they can for rebuilding. But if their military is not also replenished, then they’d be at risk if Russia tries this again a few years later.