INCREASE as the command.
That command goes to the Item and then to AutoUpdate and the binding.
AutoUpdate is probably going to say when it comes to an initial state of NULL.
If the Item is NULL, that probably means that the binding is also going to say because it has no idea what state the device is in so it doesn’t know what state to increase it from. It doesn’t even know if the device is ON. The fact that the Item is still NULL could indicate there is some problem with the device for some technologies.
If the UI element is a Slider though, even if the Item is NULL you should be able to drag the slider to a point in the range and that will send the command to the Item. Now the command is a discrete number so it doesn’t matter that the Item started out as NULL. AutoUpdate says “yep, I can set the Item to that number.” The binding says “sure, I can command the device to move to that number.”
So maybe you can achieve what you are after using a Slider and moving the slider to a specific desired point instead of a setpoint and INCREASE/DECREASE commands.