The rules, as I understood them when I cared (73.1202) was that the station
ID was
to be aired at the beginning and end of transmission,

I worked with a guy who swore an old boss of his once discovered his competitor
would sell anything, absolutely anything with no regard to its content. He
declared the boss paid for, and GOT "sponsorship" of the enemy station's
signoff message.

On the order of: "Wxxx now ceases its broadcast day. This message brought to
you by Wyyy which is on the air 24 hours if you tune over to AM 000..."

I only repeat what I'm told

Stella (make up airnames?) Starr