To 9.00 | Ps4 Downgrade 13.02

You reassemble the console.

However, the PlayStation 4 motherboard handles system updates using a dual-bank arrangement, tracking firmware across an active slot and an inactive backup slot. If a console was recently running firmware 9.00 and was mistakenly updated straight to 13.02, it is technically possible to perform a physical hardware "revert" to restore the previous state. If the console was updated through intermediate steps (e.g., from 9.00 to 11.00, then to 12.52, and finally to 13.02), a hardware revert will only take the system back to its immediate predecessor, not all the way back to 9.00. ps4 downgrade 13.02 to 9.00

Here is the technical reality: