No one knows exactly what will happen. Assuming the pension fund does go insolvent in 10-12 years and they don't do anything to fix it in the meantime. There will be at least one or two contracts negotiated before then. Granted the last contract said UPS will make up shortfall. However, UPS will not want to be on the hook for billions. (Considering they already paid twice for the pension of Central State teamsters). That part will be negotiated away. Or at least attempted to be. How many people will vote to strike for something that doesn't benefit themselves and only other retired people? A 2 or 3 dollar raise to the PT'ers or a bonus will make them vote yes.