Confusion on My H1b Interview Location

I stayed and worked till March 2012 at Mumbai. The company in USA which recruited me, applied for H1b last year when i was still working at Mumbai, so my Mumbai address is in H1b visa application as the current residence address.

My permanent residence as in my passport and the visa application is TamilNadu (near Chennai).

My H1B petition is approved and i want to fix an appointment date for visa interview.

Please suggest which location should i select for interview i.e., Chennai or Mumbai as i no longer work at Mumbai.

this is my first time applying H1B..

When in doubt, go with the location indicated on your approval notice.

Under current rules, I would expect that you can attend your interview at any embassy or consulate in your nation.