The system does not "see" that well
As I have continually found surepost package going to the same addresses or proximity stops that i am or have gone to already
and I deliver them to the post office.
it is a grievable offense of the contract and I have talked to management about it but they say it is above their pay grade.
It's that same old thing like stop counts, system has a hard time with apt numbers and suites. Also, the addresses have to be input identically. Proximity has nothing to do with it, has to be exact, doesn't care if you're right next door. System also doesn't see anything hand written like ASDs and such. Also, anything that comes out of the trailers producing a blank PAL label is not seen by the system in advance, until someone on the sort hand inputs it. If a surepost was sent to the post office package car before one of those manually entered PALs comes through the sort, there's no way they'll go dig that surepost package out of the post office route, or do a cut within the same car. No time for that.
As far as deciding, or intentionally sending packages to the post office, it doesn't happen. The computer automatically determines what goes to the post office. The only override is the clerk can actually change a surepost package to force UPS to deliver it, even without a second package for the same stop. It doesn't work the other way around.
Here's where if a package violates contractually what a surepost package can be comes into play. If it's over the weight or size that a surepost package should be, they should be bringing those pieces to the clerk to be redirected from USPS to UPS driver delivery. Buuuut, as we all know, preloaders can barely get the trucks loaded properly, asking them to keep an eye out for surepost violations is hardly a reality.
I clerked my last few years before retirement. Dealt with this daily. My building was one of the few that used high seniority drivers as clerks, full time, still earning driver's wages. We called em retirement jobs.