Incase this is useful for anyone, this is the timeline for two applications I made recently that both went to the Bootle office:
ADULT RENEWAL
Passport received 5 March
Passport printed and sent 2:14pm on 2 March 2022
Application approved 10:44am on 1 March 2022
Documents received 3:52pm on 18 February 2022
Royal Mail Tracking – Signed for 14 February
Application received 11:38am on 11 February 2022
Application submitted 11:37am on 11 February 2022
CHILDS FIRST PASSPORT
Passport received 5 March
Passport printed and sent 1:15pm on 4 March 2022
Application approved 10:40am on 3 March 2022
Documents received 9:16am on 23 February 2022
Royal Mail Tracking- Signed for 16 February
Application received 10:08pm on 14 February 2022
Identity details received 10:07pm on 14 February 2022
Email sent to person confirming your identity 8:46am on 14 February 2022
Ask someone to confirm your identity 8:32pm on 13 February 2022
Application submitted 8:32pm on 13 February 2022