Akk, OK. Yup, that is true. When you are trying to make a reservation in 2016, you are using your 2015 use year points, and can only borrow one year ahead, so your 2016 use year points, which you don't actually receive until December of this year. I agree that it can be a bit confusing. We have a February Use Year, so it's a more straightforward as to when the points are available to borrow.
Your current Use Year points were given to you in December 2015 for use up to November 2016. You can borrow points from your December 2016 Use Year for this trip, not your December 2017 Use Year. December 2016 Use Year points will be for reservations up to November 2017 (well, Dec 2016 as well), so you can borrow 2018 points for a reservation in 2017.