In the main, its mostly reports of people claiming other people are experiencing it. Where those people are, what product was bought, when, lot code from the bottom of the bag, etc are all details that aren't being provided, even when requested.
Essentially, its an unfalsifiable narrative.
Much as I appreciate Aunt Angus' efforts, and taking one in the pocketbook on this issue, I'm certain any results will be immediately dismissed unless they further the narrative. Either the State labs aren't to be trusted, or it was the wrong feed, or not the affected lots, or its not being done in CA, or...
Plenty of reasons have been put forth which would cause hens not to lay, some of which involve milling error, nutritional deficiencies, mold/mildew/"stuff" from poor storage practices or poor farming practices (or both), but none of the symptoms we'd expect from those causes are being reported, and claims of sudden onset of lay within one to two days of feed change are simply not credulous - again, there's no mechanism that would readily result in such an outcome.
