Ok, to be fair, what is it supposed to say? "Hi, you might want to wait on your boost because an update is inbound?". Yes, it sucks, especially if you don't have endless reserves and it cuts into your troop reload time. However, there will probably never be a clear 30 minute period where someone around the world isn't playing.
I think a workaround should be that any boost active when maintenance hits, should be extended for the time the game is unavailable. You could also start your troop reload when the maintenance timer gets low