The early Chapter Packs had Common/Rare cards (where in a pack, you get 3 copies of some cards, and 1 copy of the others). But later on, the format changed so that every card in the newer packs have 3x copies each.

I read somewhere that FFG had started reprinting older Chapter Packs to also include 3x copies for every card (instead of the 3:1 style from before).

Is this true?

Yes. Old chapter packs cycles have been reprinted to the 60 card (3*20) format. First, the King's Landing cycle was reprinted in this format, followed somewhat closely by the Defenders of the North, and later A Time of Ravens. The only one that's still not available in that format (or, for that matter, in any format - as many of the chapter packs themselves are out of stock entirely) is the "Clash of Arms" cycle.

When the packs are reprinted, erratad cards are usually fixed and banned cards printed with new text to keep them off the banned list.

While there's been no official word on its reprint, in a recent interview with Damon Stone at Gencon, he confirmed that they would be reprinting Clash of Arms at some point. No date or announcement yet.