and requires advanced hardware modification. Sony’s security prevents users from installing older firmware via USB or hard drive replacement. ConsoleMods Wiki
Prices for 9.00 consoles are rising, but selling your 9.60 will recoup most of the cost. This is the way to get a jailbreakable PS4. how to downgrade ps4 9.60 to 9.00
To downgrade a PS4 from firmware 9.60 to 9.00, you must perform a "Firmware Revert." This is not a simple software update via USB; it is a hardware-level process and requires advanced hardware modification
Once the hardware "switch" is active, the PS4 will boot into Safe Mode and request the 9.00 recovery firmware via USB. Risks and Warnings how to downgrade ps4 9.60 to 9.00
You must solder tiny wires to the syscon and NOR chips on the motherboard to "dump" and patch their data.