Ooooops, wrong, seniority has nothing to do with going into management. If they want you and you put in a letter, you're in if you can pass the tests and interviews. In fact you don't even need to be in the union at all to go into management, they hire some sups off the street.
I know that however most of the people in management started in the preload or local sort and then became a package car driver before moving on to management. UPS isn't going to hire a building SUP, center manager off the street. Are CEO started out on preload.
They do hire part-time Sup’s off the street.
They hire people like accountants, human resources, finance, etc. off the street.