ITB is 59 training days. Days you don't train like some Saturdays and Sundays don't count. Start to finish would depend on whether there are any holidays and how many Saturdays you train. You can go to the SOI website and figure it out from their schedule shown there.
@ Alex, I see what you mean except Thanksgiving was the 22nd, AFTER they graduated. It's possible this company company trained on weekends to finish before Thanksgiving. Since Tuesday is the beginning of their training and graduation day, that is 64 days, 9 weeks and 1 day. The first week would start on Tues and end on Mon. See how that works?
Looking at the other 4 companies, Alpha company is 72 days, Bravo is 75 days which accounts for a day off for Christmas and maybe a day for Thanksgiving, Charlie is 68 days again probably training more on weekends to graduate before Christmas, and Echo is 78 days which would account for holidays.
Marines don't get 3 day passes for Thanksgiving and Christmas during recruit training and SOI. The fallacy is in thinking the Army and Marines operate exactly the same way.
I'm not here to argue with you, I'm here to provide factual answers. Let me know if there are any other things I post which you don't understand.