I think today many regional variations are disappearing, to be honest - I guess largely due to dawn til dusk TV and all the video channels! People seem less defined by their accent than previously, except that irritating 'Esstuary' accent which seems to be taking over - even in Bradford! Bradford, btw, I've always pronounced with a clear and strong middle 'd' and no glottal stop, though I confess my 'ford' does come out more like 'fud'.
In my various jobs I've, sort of eschewed the local argot and used English....., largely because I was often dealing with people not from this area and "ey up, ahta goin' on owd lad" wasn't necessarily the best way to address customers [or answer the phone!!] I do lapse amongst family and friends but I guess I sound a bit inbetween the two.