Health and care visa

[miss jinda]

Hi,
I am a doctor and I am going to change my job to new employer with new CoS, for which I am going to apply for visa extension. My expected start date is September,2020. However, my current visa end on 20 oct 2020.
Is it possible to apply for the visa extension near to the expiry date at all.
or does it have to be a new visa before I start with the new employer?
Thanx

[miss jinda]

Hi,
I have been working in NHS as a doctor for a year now on Tier 2 general. I have to apply for visa extension with my new employer now for one year. But I came across Health and care Visa for which I am eligible.

My question is if I change to the Health and care visa from tier 2 general visa will my first year in UK(when I was on Tier2) count towards ILR or will my clock get reset?