wish it was...just checked mine and it doesn't have the downgrade option :S
I downgraded recently, and it was a hassle for me. (At least when I did it) there was no downgrade button or explanation of how to do it - well there was but it was extremely subtle and hard to find. What it came down to was finding and contacting the customer service address and stating you wanted to downgrade.
They should make billing choices as easy as accept a connection request. Forced continuity is the domain of Girls Gone Wild DVD memberships and scam artists.
I dunno, I recently downgraded and don't remember it being a hassle at all.