Had the same thing happen with one of the website sponsors. I just happened to check the order the following day to check for status when I discovered the pump I ordered was discontinued. I called to ask if I could substitute and was told I could not since the order was completed. I didn't get upset but expressed my dismay. They took my order for a substitute pump and waived the shipping charges. Like you, I wish they had told me in the first place, but I ended up getting what I wanted after giving them a polite call.