If the AI markets are to be believed, this should probably be a lot higher, since it seems unlikely that an AI that wipes out humanity would use the Gregorian calendar.

(Hint: those markets are not to be believed.)

Related market: https://manifold.markets/AnT/will-we-replace-the-calendar-by-end

Will we replace the calendar by end of 2040?

34% chance. Resolves YES if Gregorian calendar (mostly concerning years counting) is no more in use before the day that is currently said to be 01.01.2041. Resolves NO otherwise.