AA is an optional field. Originally, we made the field required, but had to change it to optional. The reason is because when the hops are located at a broker, the seller usually doesn't know the AA. They are contracted by pounds, rather than by alpha and the broker will often ship a range of alphas. Of course, if the hops are at the seller's brewery, then they should know AA. You can always message the seller directly to ask them for more specifics about any listing.