How immediate is "now"? Like, if I only have 2 hours left, I wouldn't have enough time to even give a terrible rush ending, would I? Then my only option would be "post whatever you have left and that's it."
That aside, between an obviously unfinished comic and a rushed ending, as a reader I prefer the former. This would affect how I would handle the situation. I would leave it unfinished. Terrible rush endings don't even leave any room for headcanon endings. For readers like me, an unfinished comic will be missed and remembered fondly; a comic that ruins itself with a terrible ending will be the cause of annoyance, frustration and no positives whatsoever.