Accidentally downvoted you, meant to upvote... sorry about that.
Anyhow: I was actually moving, told Comcast so, and I was indeed off the phone in a few minutes. "I wonder what everyone's concern about Comcast is anyway," I wondered. Then, a few days later, the "follow-up" calls began. It got to the point that I had to block the Comcast number just to get some peace.
It often works to ask to be put on their courtesy do not call list.
Systematically, they don't actually want to spend effort on people that don't want to talk to them and the 'courtesy do not call list' line says 'stop calling me' without inviting an argument.
It's probably more effective if you don't mind talking over their initial spiel.
I know I'll never follow up on that so I'm more focused on convincing the operator to give up on me with a minimum amount of grief and fuss (on both sides).
Anyhow: I was actually moving, told Comcast so, and I was indeed off the phone in a few minutes. "I wonder what everyone's concern about Comcast is anyway," I wondered. Then, a few days later, the "follow-up" calls began. It got to the point that I had to block the Comcast number just to get some peace.