: You can only revert to 10.01, which is still not jailbreakable. The "47 Easy Steps" (Hardware Requirements) This process is not for beginners. It involves significant micro-soldering and specialized tools. Downgrade PS4 To 9.00: Is It Possible? - Ftp
For more information on PS4 downgrading, jailbreaking, and homebrew, check out the following resources: ps4 downgrade 10.50 to 9.00
Here’s a quick breakdown of why, and what your actual options are: : You can only revert to 10
The PS4 stores the current and previous firmware versions in its chip. You can only "downgrade" if your console's previous firmware was 9.00 before you updated it to 10.50. Prerequisites Downgrade PS4 To 9
Attempting this downgrade carries significant risk and should not be undertaken lightly.
If you were previously on 9.00 and then updated to 10.50, 9.00 still exists in the inactive slot.