Consistency from batch to batch seems to be a problem even in the high end foods,
Cats will eat a food with great enthusiasm, and then you open a new case with a new batch number and they won't touch it. When I pay a fortune for food, I expect consistency to be part of the bargain, they should not be changing suppliers of ingredients looking for the lowest bidder, so the food is always different. If I wanted that I'd buy grocery store food.
I've seen it in Soulistic, Merrick Before Grain, Wellness, Blue....to name a few.
Really really annoys me.