Reg H1B transfer(never travelled to USA, in India only) and restamping

[rkanth123]

Hi Sir/Madam,

1) I have got my H1B stamped (for Company-A and in London) in nov2015 and it has validity till aug2018. I have not travelled to USA till now, I am in India .
2) Recently i got opportunity from company-B and i got my H1B transferred(cap exemption) successfully and approved by USCICS. I need to travel in December2016 to USA to work for Company-B.
3) I want to process dependent visa to my wife and 2 kids , and they will travel along with me to USA.

I have below questions/doubts. I request for your advise on this. as i am confused a lot on these questions.

1) Do i need to go for restamping, bcz of my employer is changed and i never traveled to USA on my existing H1B visa?
2) If restamping is required what is the process to get my H1B visa restamped?(drop box or personal attendance)?
3) If restamping is required what is the process to get dependednt visas(H4) for my spouse and 2 kids?
4) If restamping is not required what is the process to get dependednt visas(H4) for my spouse and 2 kids?

Thanks & Regards
RK