They did a super saturday at my hub saturday before last. They posted a list to sign up. I put my name on it. I have a fair amount of seniority. I was never called in. I work on the Night sort. When I asked management and the union about it, the answer was that they took whoever volunteered from the twilight sort before using anyone from the night sort, and enough Twilight people volunteered. I am almost certain people with less seniority than me were working. Are they allowed to discriminate based on your home shift when it comes to extra work like a super saturday? My timetable for a grievance has elapsed, I just want to know for next year... thanks.