Typically, we start to see new cameras being delivered with the update, then, if no big issues surface, it is made available for all users.
There may be additional updates as the year goes on, it makes sense that Canon wants the new camera to be a success and will add features appropriate to the price level. Don't expect them to add features that they deem appropriate only for a higher price level, that's not how they work.
The original CR announcement post quotes Canon as saying that firmware will be updated.
https://www.canonrumors.com/canon-officially-announces-the-canon-eos-r-system/