I called them and asked them if they had plans to move to a changeable system like Cypress as I was looking at buying all new equipment. IIRC they told me their system has always been changeable, in the manner you mention above. From what they told me thats the only way to change the normal opening altitude.
Typically in promode their cutter activates as high as 840' (580' if falling face to earth). So either #1 you switch it to student where it activates at 1040' or #2 you enter an altitude correction which is a DZ offset but has the same affect of setting a higher activation height.
They said this offset is remembered and used by the system each time you jump, until the offset is returned to 0'.