"By Christmas" is the only option that's guaranteed to be correct.
(Or maybe "Next year" can also be deemed guaranteed - in which case so also can "Tomorrow" ;-)
It was one of my first YAPCs when I heard Larry Wall talking about how the next version of Perl would be out be Christmas, and then I didn't think anything more about it. Christmas came and went, and I experienced the dawning realization that .. it might be a while for the next version. Like .. 20+ years. :D
As has already been pointed out, the definitive answer can only be 'By Christmas'. :)