Renewing spousal visa

[Lisa181]

Hi there,

My partner is on the unmarried spousal visa and it expires in November 2016. 9 weeks before we are meant to be travelling on a trip. I understand that we can't apply to renew his visa before 28 days of the visa expiring. Does anyone have any suggestions on how to do this within the time frame of 9 weeks?

He also has a passport from his birth country which he would be able to travel on for the trip we have to do within 9 weeks of submitting the renewal. So basically can we apply to renew his visa and whilst that is processing, go travelling on his other passport from his birth country? ( sorry I know it's very confusing) we are basically trying to find a away of avoiding the high fee for the 1 day application.

Would he be able to leave the uk and travel to another country for a 3 week trip on his birth country passport whilst his NZ passport (with spousal visa in it)is getting renewed?

Any ideas or feedback would be greatly appreciated.

Thanks