H1B interview cancellation and taking appointment in another country

Hi,

My husband & I had planned to go to Jamaica and he had booked an H1B visa appointment at the US consulate. Due to some unforeseen circumstances, we have to cancel our trip. Can he cancel his visa appointment and book it again sometime later (in another country, not Jamaica)? He is planning to go to India in March and would like to take the interview in Chennai. My question is, will the receipt be valid or should we pay again? How long can we hold on to the receipt without booking an appointment?

P.S: This would be his first cancellation with this receipt.

Regards,

RSK