All points retain their home resort advantage. So if you have 100 Poly points and 150 AKV points, only the Poly points can be used to book Poly at 11 months and the AKV points can only be used at AKV at 11 months.
At 7 months, all points are equal (with the exception of post-1/19 resale points). At 7 months, points from different home resorts can be combined to make a reservation at any
DVC resort as long as there is availability. So, using my example, you would be able to combine AKV + Poly points at 7 months to have 250 points to use at any resort.
Now, a word about resale points purchased after Jan., 2019... they cannot be used to book a Riviera nor any future resorts. And any Riviera points which are purchased on the resale market cannot be used anywhere except Riviera.