Quote Originally Posted by Psyonix
[...] OTHER THINGS TO KNOW
- PlayStation Plus on PlayStation 4 and Nintendo Switch Online will no longer be required for online play on those platforms. [...]

WHEN IS THE UPDATE COMING?!
Yes, we've been sharing a ton of info about Rocket League's next update, and you really want to know when to expect it. We'll be rolling out an update on current platforms in the next few weeks around mid September, and the launch of free to play will follow shortly after. We can't share the exact date quite yet, but stay tuned for more info. Don't forget, when free to play launches, it will only be available to new PC players via the Epic Games Store. Make sure to add it to your wishlist! [...]
Rocket League Free To Play: Seasons, New Ranks, And More | Rocket League® - Official Site