Hi all,
tl;dr - The online application for a UK passport is currently in beta, and doesn't work correctly if you're a naturalized citizen of the UK.
After reading MorganSF's thread about using check & send for your first UK passport application (
http://talk.uk-yankee.com/index.php?topic=83973.0), I thought I'd second that recommendation and also advise against using the online application system. Just to be clear, the online application is the one you can find here:
https://www.gov.uk/apply-renew-passport(I realize the link says "renew" but the page itself says "apply for, renew, or update.")
It looks like a piece of cake. You answer a few questions, and the system spits out a PDF with the pages you need to fill in and send back. I got my countersignature filled out, and sent the forms off with my naturalization certificate and US passport.
I noticed that the system didn't ask me to fill out anything about my parents or grandparents, nor was their information required on the PDF, and I figured this was because they finally got smart and realized that information was irrelevant for naturalized citizens.
Imagine my surprise a week later when I got a letter saying I hadn't filled out the entire form. I'd filled out what they'd asked for, but they didn't ask for everything they wanted to know, so now I had to fill the whole form out again, including parents' and grandparents' information. I was annoyed, but I'm British now, so I kept my grumbling to a minimum and just filled the stupid form out and sent it back. I didn't do the countersignature again, because I'd already done it, and figured they could use the one they already had.
The sharp-eyed among you will notice this was the second assumption I'd made during this process. It went about as well as the first one.
Four days after sending paperwork off for the second time, I got a call from my own personal passport case worker, saying I needed to do the whole form again because I hadn't filled out the countersignature part. I explained that I'd already done one, and she said that one was no longer valid because it all has to be on one form.
Of course it does. I was foolhardy to think the UK Passport Office could possibly use information from two completely separate pieces of paper when trying to determine whether or not to grant me a passport.
So I filled out the application a third time, and mailed it off again. Apparently this time it all went ok, because I've got a passport interview scheduled for next week.
In summary, avoid the online passport application. It won't ask you for all the information needed, and they'll wind up mailing you a new form. Instead, use the Post Office check & send service, which is well worth the £8.75 to skip all the box-checking pedantry.