I've not even thought about finishing time. Anything could happen. I'll be plodding (relatively speaking) because I'll have done a 600 the week before and the massive Pendle 600 is the week after. So, if there's trains available I'll take one, if not I'll ride home.
Hotel? For the start? Where are you coming in from?
I reckon the later start makes more sense for me. It's not like 1:30 is going to make any difference and I'd rather get more sleep.