Looks like I over egged it, apologies. I double checked with the person who told me, it's the FA proposal. Though as they set the rules it will happen.
It's per division. Eight teams up from step three, two per step three division, so a net gain of two step two clubs for 2022/23.
Edited to say an Ollie Bayliss tweet confirms this is currently a proposal and to correct some dodgy maths.