Comcast offered to lower my bill, but . .

A lot of companies are offering to reduce rates for automatic bill pay or adding on a surcharge for refusing to do automatic bill pay.  These offers come to you by mail not over the phone.  The likelihood is that the call was from a scammer looking for your banking information.  You are correct in refusing to supply it to the caller.  I would suggest calling the customer service number on your statement to alert them to the call and ask if it came from them.  If it did not, which is highly likely, please report the call to the MPD as well. They are tracking such scam calls so they can alert others to be on the lookout for scams that are currently prevalent in the community.

Yeah - I did verify with Comcast - it's a scam.  It's just weird when they know your address, payment amount and next payment date.  But all of these are apparently easy to figure out if they have your name and phone #.

They are not all scams.  Verizon lowered mine by $10.  But not for autopay, it was because I switched from credit card payment to auto debit from my checking account.   The credit card costs them, so they make the offer.  But I switched my payment method online.  $40 is way to generous an offer to be real.