To reproduce the bug, create a Command Block with a command like this :
clone ~-1 ~-1 ~-1 ~1 ~1 ~1 ~A ~B ~-C replace move
(A, B and C seem to being able to be anything to reproduce the bug)

Then put Buttons on each side of the block. When clicking them the block and the buttons will move, but we can notice that when clicking South-facing and East-facing buttons, those get stuck on powered:true after cloning.