I'm not sure that's the behavior I would want from STOP. I have certainly sent STOP requests to retailers who over inform me of every step along the fulfillment

I'm not sure that's the behavior I would want from STOP. I have certainly sent STOP requests to retailers who over inform me of every step along the fulfillment process and each overnight stop as the item ships to me. I don't want all that. I DO however want to receive notice when my item is out of stock or ready for in-store pickup if I chose that option.