Are you sure? Because a few weeks or a month ago, the AI barely played Bavarian and played Confectioner way more. I had to change my deck because Bavarian had 30HP and Confectioner had 29HP so I had to readjust certain combos to make I can beat them on the second turn. The reason I noticed is because I hadn't changed my deck from stage 5 on and I was able to get to stage 10 and clear it. Once I started grinding stage 10 for about a month or so, I noticed Bavarian was used and not Confectioner and I wasn't winning as much.
It could be just my imagination and you could be right since you are inspecting the source code but that's why I would want the devs to let us know of any updates they do to the game no matter big or small. That way I know if I'm the crazy one or I noticed small detail changes.
Yes with 1.000 % certainty ,been farming map 10 for over 8 months , the deck has not changed, same number of cards , same cards same lvl of cards . And the cards have not suffer any changes in stats. However, the way the cards are played as in frequency, one over the other, might have , i just hit auto combat always.
-------------------
Discord server for Town Of Sins - https://discord.gg/RkvQWnshpA