Ask an Immigration Solicitor. Get an Answer ASAP.
I am a solicitor.
You may apply for a document confirming your status through the Windrush Scheme, please see here (the scheme is not restricted solely to Commonwealth citizens as that is a common misconception, people such as you may also apply under it) https://www.gov.uk/windrush-prove-your-right-to-be-in-the-uk
May I help further?
You are welcome.