Well, the rule doesn't seem to be definite, as I am pushing 30, my friend is over 30, and so is some acquaintances of mine. And we all have 1000-3000 hours (2600 myself). We all got hired.
I don't know about Irish people, as I have know clue whatsoever what the percentages are.
I'm not sure if they started hiring people with high hours to get quick captain upgrades or not?