I don't have a Missal handy, so I can't give an exhaustive list, but in the Extraordinary Form of the Roman Rite, there are (I think) 2 or 3 Sundays/Holy Days of Obligation where the "Epistle" was actually a reading from the Old Testament instead of from a NT book. In addition, Ferial Days contain several extra readings from the Prophets in addition to a NT Epistle reading.
I would think (though I'm not sure) that days celebrating Old Testament figures might have "Epistle" readings from the OT as well.
The real problem, if not outright tragedy, is that most Catholics don't even remember what the Catholic Church was like from her inception in the 1st century until 1964, that is when your church leaders changed everything into something hitherto unknown, semi-Protestant and even outright unrecognizable.
Why, many John-Paul II generation Catholics probably think, the new Pope is trying to "change" the Church unaware that it was changed primarily under JPII, and the current Pope was one of the major architects of those changes. I suppose, he is doing his best to undo what the Church should have never done, fully realizing the gravity of a mistake which he authored along with others.