GRX Freestroke Adjustment

[Nomadmax]

I have a GRX 11 speed 2x set up on my gravel bike and want to adjust the freestroke (NOT reach). I have the Shimano tech docs and have gone over them a couple times. Based on the docs, the pic below should be the freestroke adjustment screw but it doesn't do anything, even when turned in either direction.

So my questions are:

Is this truly the right one to adjust freestroke?

If it is, any idea why it doesn't make any kind of change no matter how many times it's rotated in either direction?