A-Hackers-Guide
PlayStation 4

Permanence & limits

Why it’s temporary, and its limits

The PS4 has no permanent custom firmware. The jailbreak is a per-session unlock you re-apply after every power cycle, and there is no safe downgrade.

Takeaways: treat the PS4 as a per-session homebrew machine; never update if you want to keep modding; and accept that the newest firmware is usually not jailbreakable for a long time, if ever.