^Transferred points always retain their same resort identity, use year, banking deadline, and any restrictions such as resale restrictions, whenever transferred. You can transfer SSR points to the Riviera account, via contacting MS, but after transfer, they will still be SSR points in the applicable SSR use year, that cannot be used to reserve any resort other than SSR during the 11-month window, and will still have any resale restrictions that they had in your SSR account, including not being able to mix them with Riviera points at 7-months out to reserve Riviera or the new
Disneyland DVC. And the Riviera points and how they can be used will not change.
One thing to note is that the single transfer per use year rule is not applied by MS to a member's transfer of points from one account to another account the member owns, and MS has historically allowed more than one transfer per use year in that situation. However, unless you are actually intending to use the combined points to reserve a pre-Riviera resort at 7-months out, you have no reason to transfer points between your accounts.