I think 9 pm
The latest you can pick up a package is 5pm. The reason for that is...vans that return back at the station at night get audited by loading the packages into a trailer every night to get reworked again the next day. To insure that your package is brought back to the station and isnt lost, stolen, or misdelivered. If you come late at night the possibility that your package is loaded on a trailer and buried where no one can get it is extremely high. Calling ahead and arranging for a pickup is always the best option.
If you are trying to pick up a package at the Fort Mill, SC facility, you're probably out of luck. They officially close at 5pm because FedEx, for some asinine reason, decided to close a facility where people would pick up missed deliveries (likely as a result of being at work) at a time when most people can't pick it up. However, if you decide to go out of your way and drive to the location, you may be able to pick it up if they have yet to place it on a truck to deliver to the location you won't be able to pick it up at. You also may be able to arrange a pickup early in the morning, if you are ok with the inconvenience that entails. In short, you probably wont be able to pick it up, unless you go through a good deal of hurtles.
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