From the post by Chance referring to John's vid  Hanukkah Rapture 2025 (Dec 16-17, 2025) 

 The new moon was sighted for the 9th Hebrew month on the evening of Nov. 22 in Israel, that would be the first day of Kislev. 

Count off 23 days, and Sunday the 14th of December is the first day of Hanukkah on a "Friends of Zion" calendar I am using (which agrees with the Chabad.org site).  Dec. 15 is Kislev 24.

So we get 9/23 and 9/24 on the Hebrew calendar.

I have thought it would need to be somehow obvious when the puzzle is completed.