It seems that with the new law active from tomorrow no games can be played in Italy (still need confirmation but is very plausible).
So the game
Juve-Lyon
and for Europa League
Roma Siviglia
Inter Getafe
It cannot be played in Italy.
Keep in mind this is not official but probable.
And it is impossible for the UCL match to be postponed for those who play in Italy. The game will definitely continue and as you said, most likely what happened is that the game will not be played in Italy. This is really very chaotic, there has been no official response from the Italian government or concerned.