In the chapel where Benedict is hanging his zucchetto these days, and where he and Pope Francis prayed together, I noticed that the Cross is veiled in purple… probably since last Sunday, called 1st Passion Sunday in the older calendar. The icon of Our Lady should have been veiled too, but that might have freaked out… some people.
No disrespect to Francis, but I had to put the arrow somewhere.
The Ordo for the Novus Ordo also indicates that images can be covered from the 5th Sunday of Lent onward.