It has been a while but if I remember correctly ch 421 came into play when Cox was the only cable provider carrying the Hornets game and it was only available to viewers in the New Orleans area, this caused a controversy with politicians because the cable company on the north shore of Lake Pontchatrain who was a different cable provider could not get the games, When the Dish agreement was made the channel was only made available to the viewers in the greater New Orleans and surronding areas, not available to those out of the immediate area
Like I said its been a couple of years but this how I seem to remember the creation of Ch 421