This is a very interesting thread that I wish to address in multiple parts. First, in this economy I would be thanking my lucky stars to get 40 hours/week of work. The unemployment rate is over 10% nationwide for the first time in decades and apparently the "change"??? Obama promised isn't working out. We are more than 1/4 through his first (hopefully only) term and people still can't find work. I wouldn't B--- too much about only getting 40 hours when tens of millions of Americans can't get any hours.
Second, my understanding of the contract is you can only grieve OT if its extra work. In other words, senoirity will give you the right to extra work on EAMS, the pre-load, a night sort, saturday airs, or a sunday sort. But if you bid route 55A that has no pick-ups after 1600 and the guy with less seniority who bids 55B has a 1830 pick-up you have no beef.
If you want the OT I would suggest you bid the route that returns to the building the latest. It takes a certain person to want this though and I'm not one of them. I like my 8 hours somedays and my 9-9.5 other days. Perhaps an occasional 10 hour day. I don't want 11-12 hours everyday doing a 20:00 pick-up every-night, because it means you can never finish early-ever. Who the heck wants that life-style? I certainly don't!