I've been experiencing the same thing as everyone else in this thread, though the relative quietness from community in comparison to other issues makes me wonder if the AI issue isn't affecting everyone.
I've had the game since launch but haven't played much do to other obligations. I picked it up again last week and started the Elite career with Group A. The really ridiculous AI times seem to be tied to running order, at least in my case. The previous event was New England and I was last in the running order, winning every stage except for night/rain by a fair to considerable margin - almost all top 10 times on the leaderboard, at worst top 1%. Last night I did Poland and I was second to last in the running order, I won one stage, got 5th in another, and placed second in the rest of the stages. Every single second place was lost to the AI that was behind me in the running order. My pace for Poland was the same as New England, mostly top 10.
I've got two events left and I'm in first with some breathing room but if Masters is crazier than this I don't know how I can compete without memorizing the stages, which is not fun for me.