MCKINNEY ; Passport Appointment Hours. Monday-Friday. 3 AM- PM PM- PM. Saturday.Plano Main Post Office: MonFri, 9am2pm. Use the USPS online appointment tool or call 1-844-661-8730 to make an appointment. Application form DS-11: This form should be filled out but not signed until you submit it at the post office. Note: By appointment only. Passport Application Forms. Application form DS-11: This form must be filled out but not signed until you submit it at the post office. Please NOTE: The District Clerk no longer processes U.S. Passport Applications. Complete and submit Form DS-11 to a Passport Acceptance Facility.