https://www.gamespot.com/articles/ps4-550-updates-features-detailed-heres-what-it-do/1100-6456595/

Registration for the beta test of a "major" new PS4 update recently began, and now the beta is officially underway. With the update beginning to roll out to select PS4 users, Sony has announced the details of what to expect from what we now know is system update 5.50.