This kind of message would just end up in junk mail or if read deleted since the person first reading this would most likely be a customer support or similar who couldn't care less.
I believe this is time wasting and the focus should be in getting the word out to the general public and name all associated businesses (advertisers) with these news stations.
That will get their attention and if threatened enough they will stop advertising.
Sending them letters that they can handle internally will unfortunately not make any difference.
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