First child passport dead grandparents

[lilmishap]

Applying for first passports and they want MAternal and paternal grandparents. Despite me having a passport, My Dad and their maternal grandmother having a passport too. The remaining 2 grandparents are dead so Ive got to shell out for 4 birth certificates and wait an extra 2 weeks before sending documents in as I cant afford £40 a time for priority service
Or can I phone them and give them passport details for the surviving Grandparents? This seems ridiculous
They did not ask for my parents Birth certificate during MY application why do they need them for my sons?

I think it's new. I was worried I'd need to do this for dd's first adult passport as I don't know the details and don't have contact with any family so can't ask. Thankfully I didn't need to.

I would give the Passport Office a call and ask for further clarification on this point.

Were you born after 1st January 1983 or abroad?. This is usually when grandparents details are asked for.

Read it carefully, the grandparent information is only needed if parents don't have a passport in the past it used to say go to section ...

Yes, it’s if a parent doesn’t have a passport. I realised doing it for my three it was way easier to renew mine first

I needed to send mine and my mother’s birth certificates when I applied for dd1s passport. This was due to the fact I hadn’t yet renewed my own. When I did dd2s, after I’d renewed mine, I didn’t need to send the birth certificates again.

I'd double check exactly what is required.
Your passport number may well be enough, but it needs really careful reading.

I sent off for DD’s first passport last week, my DP’s passport was in date and mine expired last year. I only needed to send off DD’s birth certificate

I took the advice and phoned Passport office who couldn't work out why I was being asked for grandparents as Me Dad and my oldest DD all have Passports, I was born 1980 in London so there was no need. They want to see Paternal Grandparents documents though despite him having had a Passport (expired) and his Mum having a current one because he's 1985(?). It's a bit of a pain but it's done and you saved me a fair bit of cash so thank you all for replying!

Did you put it as you doing the application? If so, you just need your passport details as your British citizenship passes to the child. Online applications seem to default to asking for everything.