I'm not sure what changes King Arthur flours have made recently, but it seems most people are now reacting to their flours. And not just one flour, but it seems all of them.
Use extreme caution!
These have been removed from the list. The reactions are consistent and wide-spread.
One group member found out that KA had changed a line cleaner to something more eco-friendly, and right now that is the suspect.
Unfortunately, we're likely not to know more than that, since most people threw away their bags before contacting us. KA's grain they use for flour is no more risky than anyone else's grain sources, unless they know something we don't. And since the reactions are all in within a few months and consistent, we don't think it's just a bad batch here and there. We are relatively certain that there is a change within KA in how they're processing/grinding/packaging the flour, and we'll gladly add their flours back to the list once people start doing well with them again.