It is apparently possible to revert your PS4 to its previous firmware version, without any backup - Wololo.net
PlayStation 4 Release: PS4 Patch Installer released letting you downgrade/upgrade games on your console without being signed into PSN - Wololo.net
Don't fall victim to FAKE PS4 9.03 Downgrade Apps - YouTube
PS4 Syscon keys allegedly disclosed, could ultimately mean PS4 downgrade is possible - Wololo.net
How to: Downgrade digital PS4 games to version 1.0 *updated* - GamePitt -
BwE on X: "New Budget Friendly Release! BwE PS4 FW Revert Tool Allows you to patch the Syscon and NOR to complete the downgrade (revert) process. Return to your previous firmware with