She hasn't necessarily had any elecution lessons, more likely the fact that he has been away from the North East for a while now. Some people tend to pick up dialect and ways of speaking from where they are living and who is around them.
I originate from North Yorkshire but when I lived and worked in London I had to change the way I spoke because some people really didn't understand some phrases! I now split my time between Hampshire and Texas so there is even Americanisms dropped in. It's not deliberate it just what you pick up as you go along.
I actually quite like her accent. The rest of her I'm not fussed about