non eea member but family member of eea with dual nationalit

Hi every one.
Can some one give an advice. I read so many topics but could not find the answer for my situation.
As you could tell i got dual nationality british and eea. My partner got her EEA family member permit in 2010 december. I became dual national in 2015 april. My question is will my partner will lose her family permit under new law from 2012 or we still under old law which was before 2012?
As i seen here if i become british then i spoiled every thing for my partner ? We have 2 kids together and my income not as by new guidelines 18600K plus extra for each child.
Any advice would be appreciated