You can learn more about that here, but the main thing to take away is that what is now called PS Plus Essential, is essentially the previous base PS Plus service.
A user by the name of billbil-kun over on the website Dealabs revealed what they claim to be the upcoming monthly games for the now-labelled PlayStation Plus Essential service.
Another noteworthy aspect of this piece of news, is that Man of Medan is actually available in the second tier of the new PS Plus subscriptions; PS Plus Extra.
The games, which you can claim and own at no additional cost, as long as you have an active PS Plus Essential account, are stated to be Crash Bandicoot 4: It’s About Time, The Dark Pictures Anthology: Man of Medan, and the yet-to-be-released Arcadegeddon.