Help regarding ILR SET (M) section 2A Partners details

Hi

We are stuck on a couple of questions and not sure if we need to answer or not.

My husband is a British Citizen but prior to this, he was a British Dependant Territories Citizen Hong Kong. He gain British Citizen in 1989 via registration.

British Dependant Territories Citizen Hong Kong had become defunct after the handover of Hong Kong 1997 and my husband had not registered to become British National (Overseas) before deadline as he was already a British Citizen.

Question 1
Please indicate and provide details if your partner holds or has ever held any other nationality or nationalities.
Should we put British Dependant Territories Citizen Hong Kong or do we leave it blank as it is still a form British nationality?

Question 2
If you partner was not British from birth, when did they obtain settlement in the UK.
Again how do we answer this question as he was a British Dependant Territories Citizen from birth just not British Citizen. Should we put date in which he became registered as a British Citizen or leave blank?

Question 3
On what basis did your partner obtain settlement in the UK.
Do we answer by stating that he was registered as British Citizen under the British Nationality Act 1981.

Thanks in advance to anyone who can guide us with the above questions.

I think your reasoning is ok, you'll be ok putting what you think is right.