I do appreciate when the AF mechanism is upgradable with what the thread initiator suggests.
Due to unrepeatable flexure I am using with USB Focuser, I cannot achieve focus within CFZ when the focuser moves to the position it estimated in the V-curve, even when backlash is applied.
If SGP can check if the HFR is beyond the tolerance (e.g. x% of the min HFR in the V-curve), it continues to move in a small step in the same direction. If the HFR becomes larger, it reverse direction and move in a bigger step, clear the backlash, and to repeat the small step in the forward direction again.
Thank you for your consideration of the possible upgrade.