A time ago was rumored that PlayStation was going to rebuild the PlayStation Plus service with three tiers. According to Ventura Beat, the tiers will be called Essential, Extra and Premium:
Essential: the current PS Plus service with monthly games. $10 per month.
Extra: monthly games and a game catalog of hundreds of downloadable games. It looks like the games available on PS Now transferred to this service. $13 per month.
Premium: monthly games, game catalog with streaming capabilities and a library of classic titles and game trials (similar to the service offered by EA on EA Play). $16 per month.
We should know more from Spartacus in some weeks.
Thanks, Ventura Beat.