This location's hours changed on Oct 12, 2019. They are now open 7 am to 9 pm M-F, 9 am to 6 pm Sat, closed Sunday. This was done to make the OKC PO with late hours more central to OKC (the Airport PO used to have the late hours).
What happen to 11pm
I think most are open from 8 to 12 noon. If it's a small station it may not be open at all.
They are only open Monday - Friday
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