Your points don't drop into your account on the first day of a new Use Year, they are already in your account (or will be, once you close on the sale!). Your contract comes with many years' worth of points, each with a set of dates associated with them.
Your Oct 2017 UY points are valid for stays from 10/1/2017 to 9/30/2018; they are valid for stays from now until 9/30/2017 if you borrow them or for 10/1/2018 to 9/30/2019 if you bank them.
Your Oct 2018 UY points are valid for stays from 10/1/2018 to 9/30/2019; they are valid for stays from 10/1/2017 until 9/30/2018 if you borrow them or for 10/1/2019 to 9/30/2020 if you bank them.
The list goes on for the rest of your points, through the last full year of your ownership.
You can book a stay 11 months from check-in when using your OKW to book OKW and 7 months from check-in when using your OKW points at another resort regardless of your Use Year. For example, to book a stay with a check-in date of June 15, 2018, you could make the reservation on July 15, 2017 if booking at OKW or on Nov 15, 2017 if booking a different resort. With an Oct UY, that stay falls within your Oct 2017 UY. You could use Oct 2017 UY points to book that stay and/or banked Oct 2016 UY points and could also borrow points from your Oct 2018 UY if you needed to do so.