okay noted no taxi. should I delay it a day because of new years, I don’t want to get turned away because a hungover chef-corporal?I'd make it around 10 o'clock, it gives you enough time to have a big breakfast and then do some loosening up exercises. Don't forgot that the January 01 202 2, everyone will have a hang over, give them a little time to get over it.
BTW, I did a video, which gives the history of Vauban's Forts around Paris, you might like to check it out, at least you'll know why it is there.
I repeat, do NOT get a taxi to the fort. Go on the metro, you have got 3 days in which to find the place.