Sounds like the New England negotiator was smart.
Just to clarify so I understand: in New England, vacation earnings are calculated on a true calendar year. So if a new hire was hired in March, the weeks he wasn't employed in Jan and Feb would not count against him and would reduce 1/52 to 1/44 (or however many weeks there were)? That makes sense.
Since the supplement I am familiar with calculates on earn dates which are tied to employment/FT dates and not Jan 1, there wouldn't be any weeks where the employee wasn't employed by UPS. If the employee was laid off, out on leave, or took unpaid time off, those weeks calculate in as a zero to reduce the overall 1/52. (I wasn't around for the strike so I don't know how it was handled but there are a couple of exceptions where the $0 won't factor in such as military leave.) There is no 20/40 hour guarantee....if your 1/52 calculates under that, that's just the way it is. If it calculates over that, great.
Browniehound: it's only a win-win for the FT employees with OT or the PT employees who get a lot of hours. We do see quite a few PT employees who end up with a vacation check that is less than 20 hours x their rate because they don't usually get to work 20 hours each week. The 3.5 hour daily guarantee (if they get it) would only give them 17.5 hours per week.
Once again, I'm fascinated by how much the local riders differ from area to area. I've only worked with one group that used 1/52 and we thought they were the oddballs. All of the rest of our locals are paid hours x rate for vacations though the number of hours do vary based on local.
OP: I hope this has helped. If you still aren't quite satisfied (it's hard to give you specifics when we don't know the details), ask for the payroll inquiry. You can even ask them to send you the history showing your wages and how your 1/52 was calculated. Good luck!