I checked it yesterday.
You can find those cards from [MINOR SPOILER]
The merchat that you saved from the griffon in the prologue area (the first/only village)
I'm not entirely sure about this but i think those are the cards that you were able to buy from Elsa, during the prologue, the same cards that you weren't able to find anymore if you missed it the first time around.
By the way, if you are one of those people who was having really big trouble winning in gwent matches...trust me, go buy those cards...
I was literally struggling against every single person on that minigame, and after i bought back those 3/4 cards i really started to be competitive
The wording in the patch notes are a bit ambigous. It simply means that you can purchase the cards from the prologue at the mercant now. Otherwise they would be unobtainable if you didn't play Gwent during your days in White Orchard.
I don't know if there's confusion on this or not. It has been confirmed that Bram (the merchant with the horrid bowl haircut) DOES have the Gwent cards for sale that Elsa had. Since you can't talk to Elsa after the prologue this is the way to pick those cards up after you've already finished the prologue. When I went back, Bram had nothing for me, but that's because I had already purchased those cards from Elsa before the end of the prologue.
As far as "new" cards in the prologue, I can't figure out what those are or where they are or if they even exist or if there's just confusion on the wording for the duplicate cards Bram now has. If someone has info on these new cards, clarification would be greatly appreciated.
---------- Updated at 04:30 PM ----------
Oh cool. Someone posted right before I did so I didn't see it. No new cards. Nice to know. Thanks for the clarification.