I initially wanted to do a paper application after I took regular passport size photos, then found out the online application required a digital photo. I ended up doing the online application because I realised there really wasn’t much of a price difference with both methods, even after retaking digital passport photos

so here is my timeline...
Passport for: Adult first passport after Naturalisation
Applying from: UK
Method of Application: Online
Date of Application: 13 Nov. 2019
Date Identity Verified: 14 Nov. 2019
Date Documents Sent: 14 Nov. 2019 (Royal Mail next day, signed for) to Cardiff
Date Documents Delivered: 15 Nov. 2019
Date Documents Received: 15 Nov. 2019 (15:29)
Application processing: 15 Nov. 2019 (15:48)
Application Approved: 22 Nov. 2019 (10:17)
Passport Printed and Sent: 22 Nov. 2019 (15:51)
Date Passport Received: pending
Date of Return of Documents: pending