There are exceptions.
Needed a new passport in a hurry so used the same-day service. Most of it can be done online, including uploading a photo.
You're then given an appointment time. So traveled up to London on Friday. Seen on time and showed old passport and proof of ID, Given a ticket with a return time 4 hours later.
Went back at appointed time and picked up passport.
Very efficient operation. No waiting and friendly and helpful staff.