Complicated Question - Proofing my permanent residency

[Dorota01]

First of all, thank you so much for helping me getting citizenship. Yes, after nine months, I became a British Citizen. I am grateful to be part of this forum, and I appreciate all the help I received from the staff and all members. Thank you
I would like to ask for your help once again please and ask you if I can apply for my daughter's British Passport directly or I have to register her as a British citizen (form MN1 and almost £1000) first?

The situation:
I have a second daughter living in the UK, although not staying with me since leaving for college last year. Cutting a long story short, she was born in the UK in 2004 and had been continuously living in the UK since. She is still attending college, having a Polish Passport and Settled Status for more than a year.
The problem is that for me to apply for her British Passport, I would have to provide the below first:

Evidence that at the time of the applicant's birth, parents held:
• Indefinite Leave to Remain
• Indefinite Leave to Enter
• No Time Limit

The issue is that I never officially applied for Indefinite Leave to Remain because Poland joined EU in 2004 and before that, I was a Direct Family member of an EEA national.
Now I am a British, and I cannot prove (provide evidence) that I did hold Indefinite Leave to Remain at the time of my daughter's birth.
The only thing I have to prove my residence from those days is the HMRC Employment History record showing different companies I worked for and my National Insurance contribution. I was a working parent for most of the time. The only time off I had was 6-month maternity leave which I took twice after my daughter's births. Her dad lives in Spain with our other daughter (Spanish national).
Hypothetically I did acquire automatically permanent residence after living in the UK for the first five years and exercising the Treaty Rights. Still, I did not apply for physical proof.

Do you think that the HMRC Employment History record will be enough to evidence my legal residence in the UK in those years? Unfortunately, I don't have any other documents. I lost all my payslips and P60s from those years.
What options do I have? Do you think HO would accept/allow the automatic permanent residence?
Or the only option is to register her as a British citizen using the form MN1?
I am in a difficult financial situation and spending almost £1000 would be impossible.

I would be grateful for any help. Thank you

[Dorota01]

BTW: My still husband is a Spanish citizen who also hasn't applied for the Indefinite Leave to Remain in the UK. In fact, he never applied for the Settled or Pre-settled status as well since he left for Spain.

[secret.simon]

The concept of automatically acquiring PR was only introduced into UK law via the 2006 EEA Regulations. So you can't have acquired it before your daughter's birth in 2004 (because it did not exist at the time).

Between 30th October 2000 and 2006, EEA citizens were not eligible for most forms of permanent settlement in the UK.

Prior to 30th October 2000, ILR was available on request for EEA Citizens working in the UK and also, any proof of working in the UK prior to that date would be taken as proof that the EEA Citizen was settled in the UK. However, prior to 2004, Poland was not a part of the EU and therefore you, as a Polish citizen, will not have had that status.

As the child's father was a Spanish citizen, if he has proof of working in the UK before 30th October 2000 (payslips, P45s, P60s, etc) AND proof that he was not absent from the UK for more than two years before the child's birth, that should be sufficient to prove your child's British citizenship.

See from Page 22 of the European Economic Area (EEA) and Swiss nationals: free movement rights guidance.

If you or your husband don't have ILR stamped into one of your passports dated to before your daughter's birth OR any of the proofs suggested above, she is not a British citizen and would need to be registered as a British citizen on Form MN1.

[Dorota01]

The concept of automatically acquiring PR was only introduced into UK law via the 2006 EEA Regulations. So you can't have acquired it before your daughter's birth in 2004 (because it did not exist at the time).

Between 30th October 2000 and 2006, EEA citizens were not eligible for most forms of permanent settlement in the UK.

Prior to 30th October 2000, ILR was available on request for EEA Citizens working in the UK and also, any proof of working in the UK prior to that date would be taken as proof that the EEA Citizen was settled in the UK. However, prior to 2004, Poland was not a part of the EU and therefore you, as a Polish citizen, will not have had that status.

As the child's father was a Spanish citizen, if he has proof of working in the UK before 30th October 2000 (payslips, P45s, P60s, etc) AND proof that he was not absent from the UK for more than two years before the child's birth, that should be sufficient to prove your child's British citizenship.

See from Page 22 of the European Economic Area (EEA) and Swiss nationals: free movement rights guidance.

If you or your husband don't have ILR stamped into one of your passports dated to before your daughter's birth OR any of the proofs suggested above, she is not a British citizen and would need to be registered as a British citizen on Form MN1.

Thank you @secret.simon all the info, very much appreciated.
It sounds like I will have to put together £1000 and apply for my daughter's British citizenship using the MN1 form after all. Unfortunately I don't have easy relationship with my ex so getting any proof that he was working before 30th October 2000 would be close to impossible. Once again, thanks a lot.