Hate to say it..With 20 in and 10 to go and still a supervisor...you are in the (target) group.
Expect a buy out before 2023, they will be thinning out the herd before eliminating further funding to your pension plan. Their final goal is to lessen the number of active participants before that date, saving additional paperwork and cost.
Your twenty will be there if you decide to stay, you have rights under ERISA, you will have three options:
A Stay and stick it out..stuff that 401k match to the max and get out at 65 when you become eligible for that vested time and also Medicare.
B. Take the buy out, which will not include any retirees’ health and welfare coverages and go to greener pastures. You will not be eligible for any future pension benefits also, study the history of previous buyouts and choose wisely.
C. Stay till you drop, if you make it to age 70 1/2 you will be required to collect your pension benefits under the UPS Retirement Plan, you can triple dip .. SS at 67 ... pension at 70 1/2... and your salary without any penalties except the standard income tax...Only the brave and sturdy or stupid takes that option...
I would choose option C if you are vindictive or mad enough to get back at the company on how they are treating you for your loyal years of service.