I've been battling this for nearly a year (since ACA 2015). We leave all of our 1st floor walls on the pre-set A-Wall layer. Our 2nd Floor walls are on a layer we've created (2nd-Wall). Even if the walls on the A-Wall layer are turned off AND frozen while we're working on the 2nd floor, if we do ANYTHING to our 2nd floor walls (move, copy, mirror, stretch, etc.) the A-Walls automatically turn on and unfreeze.
I can't for the life of me figure out why. We did not have this problem in ACA 2014.
All help is appreciated.
Cheers,