It all started with this post from The New York Radio Message Board:

CBS-FM to change formats at 5PM - Glenn 16:36:21 06/03/05 (0)

Posted by Glenn on June 03, 2005 at 16:36:21:

WCBS-FM is flipping to Jack today at 5. Tune in!


It is June 3, 2005 and JACK has arrived, CBS-FM is dead.

Here are some great posts from the New York Radio Message Board analyzing the implications of this decision: 

"Conversation with Bobby Jay" by VINCE SANTARELLI 

"MY LAMENT" BY ALLAN SNIFFEN

"AMAZING" BY KC JACKSON

"WHEN CLASS STILL MATTERED" BY JOSEPH M

"Harry Harrison's Good-Bye From The Bergen Record" Posted BY ALLAN SNIFFEN

Analysis in "Radio & Records" on why WCBS-FM changed format


[John F. Porcaro's Radio History Pages]