The FCC takes cable leakage seriously, every cable service provider has to file a form 320 with the FCC annually that certifies that they are not leaking. Although the FCC is obsessed with the aeronautical segments of the band 108-137 and 225-400 MHz any leakage is an issue.
Comcast is usually good about technical operations and maintaining their plant but a lot of the other operators can be real hacks. But all of them know for certain that leakage and the FCC can add up to big fines.
Almost every company owned truck by cable operators caries a leakage detector receiver that’s set to detect a carrier that’s injected at the head end so if they drive by a leaking section they can identify and eventually repair it.
Notify the FCC directly at
https://consumercomplaints.fcc.gov/hc/en-us and try entering it as a problem affecting radio, or call the cable operator directly although that can be often an issue trying to reach someone who understands what you are talking about but if you do reach anyone involved with the technical side of the plant you are doing them a favor.