Doesn't seem to be form
SET(F). It specifically states
Indefinite Leave To Remain In The UK as a Child Under the Age of 18
(A Child over 18 may also be Eligible, See Section 23 of The Guidance Notes) and a Biometric Immigration Document
The
Guidance Notes states:
For Which Applications Must You Use Form SET(F)?
Form SET(F) must be used to apply for indefinite leave to remain in one of the following categories:
- Child under the age of 18 of a parent or parents or a relative present and settled in the UK
- Adopted child under the age of 18 of a parent or parents present and settled in the UK
- Child aged over 18 of persons present and settled in the UK
You must be in the UK to apply.
2. Qualifying For Indefinite Leave To Remain
To qualify for indefinite leave to remain in the categories for which you must use form SET(F), you must meet the requirements set out in the following parts of the Immigration Rules:
Part 8, Section 2 - Child under the age of 18
Part 8, Section 3 - Adopted child under the age of 18.
So, almost certainly it is not SET (F).
You could try
SET (O), which covers "Other purposes/reasons not covered by other application forms".
You may also want to read the following;
https://www.gov.uk/join-family-in-uk/eligibility
https://www.gov.uk/remain-in-uk-family
My feeling is that your research has led you to the rules in place before July 2012, which allowed parents to get ILR immediately. Now, not only is it difficult to get a family visa for them, it does not give them ILR, but limited LR for a renewable 2.5 year period. They will need to renew it four times (for a total of 10 years before becoming eligible for ILR. Remember that when applying for limited LR, they will also need to pay £500 per application to ensure access to the NHS.
If either your partner or you are a British citizen, look into exercising the Surinder Singh route (google it). I see absolutely no hope for you under the UK Immigration Route.