The bishops or the congregation can't really make the rules. All Catholics over the age of 14 are supposed abstain from meat on the Fridays during Lent. This has been the standard since the days of Vatican II. They are also supposed to fast (no eating between meals, smaller meals, no meat) on Ash Wednesday and Good Friday.
I know in the past when St. Patrick's Day fell on a Friday in Lent, the Archbishop of New York City would sometimes give a dispensation to allow people to eat corned beef since St. Patrick is the patron saint of NYC. But it wasn't automatic, and it didn't happen all the time.