Unfortunately the elephant in the room is that Trump might win and basically hand Ukraine to Russia. Of course it won’t be that easy. Many European countries would try to fill the gap like France and Poland but eventually it won’t be enough and EU countries might have to put force in Ukraine to stem the flow. I think Biden is getting ready in case that happens (not that it will but it could happen) and want to leave Ukraine in a good place before the election. If Biden wins, Putin better just declare a ceasefire