ILR Question - Set(M) or Set (O) Form

[Menezes]

My husband holds a PBS dependent Leave to remain Residence permit . He would like to now apply for a ILR since he has completed 5 years in the UK. He came to the UK as a dependent of me. I came to the UK as a Tier 1 General PBS holder and got my ILR in Nov 2016. He got an extension on his visa in Feb 2018 as a PBS Dependent. He went to the government website and after answering a few questions he was directed to complete Set (M) Form. but then it says do not use this form if your current leave to remain is as partner of PBS. Could you let me know if he should complete Set (O) or Set (M)?
Many thanks.

[zimba]

My husband holds a PBS dependent Leave to remain Residence permit . He would like to now apply for a ILR since he has completed 5 years in the UK. He came to the UK as a dependent of me. I came to the UK as a Tier 1 General PBS holder and got my ILR in Nov 2016. He got an extension on his visa in Feb 2018 as a PBS Dependent. He went to the government website and after answering a few questions he was directed to complete Set (M) Form. but then it says do not use this form if your current leave to remain is as partner of PBS. Could you let me know if he should complete Set (O) or Set (M)?
Many thanks.

SET(O)