Stepper #1 is the worst case scenario as far as multiple rotations (each rotation has a chance to return the same absolute position code).
Gear Ratio 6.0625
Min angle -3.05433
Max angle 3.05433
If the last known position is within +/-.011757 radians of the current position there is a 98% chance the joint has not moved and does not need to be recalibrated to establish joint position.