Aparently when you craft a exceptional sack of flour and put a bunch of normal ones on top, it retains to all the exceptional atribute. It is also true that when you split the stack one half retains the atribute and the other dont, for last if you put a normal stack into an exceptional one, you lose the exceptional atribute on all items.
here a gif showing more about the issue. This do not occur on dough you cannot stack the exceptional in the normal one and vice versa.

here a gif showing more about the issue. This do not occur on dough you cannot stack the exceptional in the normal one and vice versa.
