Is your partner a UK citizen, or foreign national holding indefinite leave to remain?
Thank you for your question and patience, I’m Tom and I’ll try to help you.
Yes, that is absolutely correct. You would have to apply using form FLR(M) because you are already in the UK and you wish to apply for leave to remain on the basis that you are a spouse married to a UK national.
My goal is to provide you with a good service. If you feel you have received anything less, please reply back as I am happy to address follow-up issues specifically relating to your question.