Updates:
I am going to update the previous reply so that it is representing some new changes in order to keep the picture all together for Charleston, SC locator 34 processing center. For the other applicants at other processing centers: please note that Charleston's processing center is one of the slowest processing centers, especially with the routine applications, so please be careful as you compare it to your own processing center at some other location or as you draw any conclusions.
Here are a few timelines with locator 34 in Charleston, SC and hopefully that will give you some idea of how long it is taking for approval at that location these days. I am providing the day of the application at USPS/library/county office and the day in which approval was indicated (if any). I am also including whether the application was expedited or routine service. All the approved applicants received their passports within 3 business days post approval date.
ROUTINE APPLICANTS:
Applicant 1) Applicant applied on 4/2/21 at USPS --- Routine service --> approved 12 weeks later (June 25).
Applicant 2) Applicant applied on 4/2/21 at USPS -- Routine Service --> approved 11 weeks later (June 18).
Applicant 3) Applicant applied on 6/21/21 at a County/Library office -- Routine Service --> Approved 10 weeks and 5 days later, or approximately 11 weeks later on (September 4th).
Applicant 4) Applicant applied on 6/28/21 at City hall -- Routine Service --> Approved 11 weeks + 4 days later on (September 17th).
Applicant 5) Applicant applied on 6/29/21 at USPS -- Routine Service --> Approved 11 weeks + 2 days later on (September 16th).
Applicant 6) Applicant applied on 7/6/21 at USPS -- Routine Service --> Application is still in process after 10 weeks+ 3 days (Should wait for 1 week).
EXPEDITED APPLICANTS:
Applicant 7) Applicant applied on 6/10/21 at USPS -- Expedited Service --> Approved 4 weeks + 1 day later (July 9).
Applicant 8 ) Applicant applied on 8/17/21 at USPS -- Expedited Service --> Application is still in process after 4 weeks + 3 days. (Application is expected to be approved, I am guessing, within 1 week, based on the previous expedited approved service.
Applicant 9) Applicant applied on 8/21/21 at USPS -- Expedited service --> Approved 3 weeks + 6 days later, almost 4 weeks, on (September 17th).
Applicant 10) Applicant applied on 8/23/21 at USPS -- Expedited service --> Application is still in process after 3 weeks + 4 day. (I am guessing that this applicant should wait to the end of next week before any expectations of approval and hopefully they will be approved within that time frame).
I hope that answers your questions in regards to Charleston, SC's processing center.