You will need to go in and ask in person, GP post office doesn't answer the phone, even if you get the right number (the one on the USPS page is disconnected lol)
It depends on the route assignment. Some routes do in fact p/u and deliver on Saturdays while others don't. Best bet would be to call the post office directly and see what your schedule is.
Other post offices do. Grants Pass post office doesn't do anything useful.
Thanks! Your answer is awaiting moderation.