Don’t know if this helps. When I rang the passport office this morning, I asked about this, and they said once you send them in, they get uploaded guessing normal time to be put on the system, and then the examiner will look at them and as long as all is okay will then approve it. The application doesn’t go back to the bottom of the pile, so from what bloke was saying on the phone, once you send them in and it’s been acknowledged it’s a fairly quick process