Sounds exactly like the guy I spoke to except he said use the online form then hung up as I was still speaking lol, lost a customer here I won't use again no need for rudeness especially after holding for 30+mins...
The OUT OF STOCK email you must have had references the sticky Gibbo thread, and gives a direct link to the form to request cancellation. The sticky thread references that very same form; it's the most efficient way they have to deal with these requests as they're being swamped with customer support requests. Why are you calling them to request cancellation?