H1b to H4 EAD

I am eligible for H4 EAD visa- because my husband has completed 10 yrs of working and basically meets the criteria for me to be on H4 EAD. Currently I am on H1-b Visa.

I am planning to convert from H1 to H4 EAD.

My Husband’s H1-b visa is in the renewal process and requires stamping on our next visit to India.

Can I apply for H4 EAD before the India trip- scheduled in November 2015? Or should I convert to H4 right now, go to India, get the H4 visa stamped, My Husband gets his H1-b visa stamped and then in December 2015 when we return back, I apply for H4 EAD?

Please advice!!

Thank you!!