If you used 12 speed Ultegra rings there should be no difference. Are you certain you didn't put the small ring on incorrectly?

On the 11 speed rings there is a mark that lets you know. I routinely have swapped 11 speed 105 and Ultegra rings on my 105 crank with no issue for my Di2.

Chain line doesn't change. So there is no reason why the RD settings should be changed. And that you did or intend to change them also lends credence to the ring being installed wrong or you changed something up front that affected the chain line when it should not have.


Or did you also do something at the rear of the bike at the same time you installed the rings?