Change TuyaCoveringCluster attribute

Who can help me with the following:
I have a Tuya (Moes) controller for opening and closing my sunscreen. Unfortunately it takes more time to close the sunscreen then to open. I currently solve this by manually edit the value of attribute: current_postition_lift_percentage.
I am looking for a way to change this with an automatization. E.g. adding an extra 15 percent when it opens.
Anyone an idea if this is even possible?

Btw I tried to make this happen with the ZHA Toolkit, but so far I was not able to get it working.