Processing H4 visa while having expired H1 visa

[Kbanat12]

Hi,

I have H1b visa which got expired in Feb 2016, but still few years are left as i have not yet completed whole 6 years in US.
I am currently on maternity leave till december 2016 in India, and my husband will be travelling to US in August. So I was planning to accompany him on H4 dependent visa. And then once my leave is completed, I was planning to work on H1B visa with my current employer.
So my questions are
1) Once I get the H4 visa will my H1b be cancelled?
2) Can I initiate a new H1b visa without cap from US itself or do I have to come back to India?

Please reply.

Thanks