He reportedly was in the building preparing for his show, and was told shortly before 1pm.
http://www.philly.com/philly/blogs/real-time/Josh-Innes-is-out-at-941-Sportsradio-WIP.html
http://www.philly.com/philly/blogs/real-time/Josh-Innes-is-out-at-941-Sportsradio-WIP.html