You can bank any or all of your points, using as many separate banking transactions as you desire, from one use year into the next one as long as any banking is done by no later than the end of the 8th month of your use year.
In relation to any reservation that is to take place in a given use year, you can, if needed and regardless of whether you have previously banked points, borrow points from the next use year, but you cannot borrow from that next use year points that have already been banked into it.
In your situation, when you are still a long way from the eighth month of your use year, it is usually fine just to wait a while to bank if you think you might still want to make another reservation during the current use year. You only need to bank early if you want to actually use those points for a reservation you will be making in the next use year, e.g., you decide today to make a reservation in Sep 2023.