With only one change allowed, I'll bet as late as possible (= end of December). We may have more information in the meantime !
EDIT : I deleted my post in the other thread as requested by Fabien.
Bahhh, you're no fun! But ok, as it is within the rules.
I put an end of year deadline for initial bet to try and get everyone's opinion in given the current situation (before first flight??), which is what I'm most interested in. But obviously we don't have a lot of information. By the start of next year, I believe we'll know enough to have a more informed guess which is why everyone gets a chance to modify their bets. No changes after mid-next year.