Originally Posted by
JandM
All you will need to do is tell INZ that you have a new passport with (whatever) number, and they will put the visa into it. You can notify them while your case is still being processed, but it won't make any difference until the time comes for putting the label in. As yanyan881 says, show them both, then they'll know it's still you, who applied quoting the other number. (That sounds odd, to have two passports "live" at the same time. As you're saying it's due to a new regulation in your home country, I think I would see if I could find a website or leaflet explaining the situation, and send that along, too, in case whoever at INZ deals with the case has not heard about it.)