Form AN - Biometric fingerprint date?

I'm quite happy that I've been a married resident long enough to finally be applying for citizenship!  However...  Question 6.13 on the application form asks for the date my Residence Permit fingerprints were taken.  I have no idea beyond it was in early 2014.  There was no officially appointed date, I simply popped down to the London Bridge Post Office at my convenience.  I phoned the Post Office today on the off-chance they might have kept a record of names and dates such documents and fingerprints would have been forwarded to Home Office, and they said they don't keep such records.  Indeed, they said the Home Office would have that information!  I'm trying to avoid the time waste of submitting my fingerprints (yet again!), and thereby delaying the citizenship processing. 

The questions are quite detailed in comparison to all the earlier forms in this entire process, and I assume I can't simply leave it blank.  I've completed all of the other information regarding the Residence Permit, it's only the fingerprinting date I can't recall.

Is there any advice, or insight anyone can share?

You'll have to re-enrol your biometrics as a part of your application, just so you know.

If you don't still have the paperwork, you'll just need to estimate the date as best as possible (month/year).

Thank you for the response.

What do you mean re-enrol?  I know I need to submit my current Residence Permit, but do you mean in addition to that, I will need to submit fingerprints again regardless?

I still have the original paperwork which requests my submission of photo/fingerprinting for my permit, but it just states within 15 day to be fingerprinted; no specific appointments were assigned.  You think best-guessing the date of my original submission will be okay?  In a way it's all rather a moot point if I need to be fingerprinted again anyway.   

Had I known there would be so many hoops to jump through, I would have worn sneakers.   

Thank you for the response.

What do you mean re-enrol?  I know I need to submit my current Residence Permit, but do you mean in addition to that, I will need to submit fingerprints again regardless?

I still have the original paperwork which requests my submission of photo/fingerprinting for my permit, but it just states within 15 day to be fingerprinted; no specific appointments were assigned.  You think best-guessing the date of my original submission will be okay?  In a way it's all rather a moot point if I need to be fingerprinted again anyway.   

Had I known there would be so many hoops to jump through, I would have worn sneakers.   

Best guessing will be fine. Just write month and year.

And yes, you will need to give fingerprints again to prove you are who you say you are and to prove you were who you are now. For example, I've given fingerprints at least 5 times! But it is to prove I am me and not someone else - think of it like how iPhones use a fingerprint to unlock your phone.

Thank you!  The iPhone is a good analogy.   

I'm quite happy that I've been a married resident long enough to finally be applying for citizenship!  However...  Question 6.13 on the application form asks for the date my Residence Permit fingerprints were taken. 

Are you applying for citizenship under EU rules or UK immigration laws? Resident Permit is EU laws and has different requirements.