Here's an interesting talk by Ajahn Amaro, present abbot of Amaravati monastery in England. "The breakthrough" is what he calls stream entry. Here are links to the talk and to the succeeding Q&A.

I found these helpful in understanding the perspective of a seasoned Thai forest monk (Ajahn Amaro was a disciple of Ajahns Chah and Sumedho). Not surprisingly, the destruction of the first three fetters are considered the mark of stream entry. He also expounds on what this means in his tradition.

I actually cant listen to his voice! haha!

Im english also, and I think it must just remind me of a certain type of annoying person (people) from my past. Maybe an annoying partronising guy in sandles at a church cake sale or some annoying know-it-all super enthusiatic camper at a campsite ! 

What stage on the path does this innate aversion or irritation to inexplicable things about people disappear on the path?

Haven't quite finished it, but appreciated what I heard. It's always helpful to be reminded that stream entry is a very realistic goal, and in this lifetime.

I wouldn't be put off by Amaro's voice. That's a very small reason to deny yourself a worthwhile listen. A nice talk to go along with this is Ajahn Amaro reading the transcript of Ajahn Chah's "It Can Be Done" dhamma talk.