Unless you can find a job with comparable benefits and the opportunity to make six figures a year in the future I would stay where you’re at. Preload sucks, I know. It takes time to get into full time driving. Even when you’re RPCD you will be covering routes in the blind, at times it can be overwhelming. If you stick it out, get your time in you’ll eventually win a bid on a decent route. Or perhaps you stay cover, it won’t matter once you reach top rate and you’re making more than all your friends that have four year degrees.
The pension, keep that in mind. You’ll never have to worry about medical debt either. Keep grinding, you’ll get there.