Thanks for your question. I will try to help.
Unfortunately, because you switched to a spouse visa your ILR clock on an ancestry basis was effectively stopped.
This means that you would only qualify for ILR once you have spent 5 years on your spouse visa (no time in other visa categories is permitted to count towards ILR on the basis of a spouse visa) OR once you have spent 10 years in the UK with leave to remain .
So, you would certainly have to apply to extend your spouse visa so that you can reach 5 years residence in the UK on a spouse visa. Once you reach 5 years you can apply for ILR under your spouse visa.
I suppose that you would probably also reach 10 years legal residence in the UK at around the same time that you reach 5 years on your spouse visa, but I would still apply for ILR under your spouse visa because the 10 years ILR route obviously carries a much more demanding evidential burden since you have to prove you have been here for the whole 10 years.
Sorry I could not have better news for you, but if you extend and then apply once you reach 5 years on your spouse visa you will be fine.
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