I actually answered though I usually don't answer strange numbers. Great deal on upgrade of my comcast account. It was good timing as my last promo of 6 months ends this month. The lady had access to my account knowing my start date. I was suspicious and wouldn't give any personal information if they asked... but they never asked. I upgraded but have yet to receive my upgrade contacted support online and there's no record of my upgrade at all. I don't think this is legit at all, but I don't know what the scam is if they did not get me to give them anything over the phone. Very very odd.
I got a call for the third time this week - no voice mail, no one spoke on the other end when I picked the phone. Looks suspicious to me. I would not give out any info to them.