Hard to say, n'est-ce-pas?
As I type, he's only a few miles from the start, with just under 3 hours to get there. [I presume someone else - mainly FidgetBuzz? - has done 90% of his paperwork for him, he just needs to swap bikes. ]
It would be fun to hang-out at the start with everyone else for a couple of hours, drink some champagne etc!
Or he could get a few zzzzz under a tree.
If I was a betting man ... I'd say he will do laps of the environs for as long as poss. And he will ride straight thru the first night for a decent kip early tomorrow night. (Possibly in the Support Vehicle?) That should be *well* over 420 miles for the 2 days, so he can finish PBP knowing HAMR is still on schedule.
(But I'm not! )