Part of a task assignment rotation program that I'm building includes the ability to add a "skip". A technician can still be in the rotation to be assigned a task. 
When the Assign Task button is pressed, the Skips field is decremented by 1. Obviously, this should only happen if the value of the Skips field is greater than zero.
I have a Rule for Field Definition set up, but cannot get it to fire when the form updates.