PLT TOWING BANNER OVER DOWNTOWN DENVER ENTERS STADIUM TFR.

Narrative

I WAS HIRED TO FLY A BANNER IN VIEW OF DOWNTOWN. I LEFT ZZZ ARPT WITH BANNER IN TOW. I ARRIVED IN THE DOWNTOWN AREA AND MADE A PASS IN THE VICINITY W TO E. TURNING BACK W FOR 1 LAP BROUGHT ME INTO THE SUN AND A HELI PASSED CLOSE BY; SO ON THE NEXT LAP I WIDENED MY LAP ALL THE WAY AROUND THE DOWNTOWN AREA. I FLEW OVER A PROFESSIONAL BASEBALL FIELD AT APPROX XA00. MY NEXT LAPS WERE OVER THE FESTIVAL AREA AND ON MY 4TH LAP I NOTICED THE LIGHTS ON AT BASEBALL FIELD. IT WAS APPROX XA15 AND I THEN REALIZED THAT THE LCL BALL TEAM MUST BE BACK IN TOWN. (I HAD BEEN UNAWARE THAT THERE WAS A GAME ON THIS DATE.) I LEFT THE AREA IMMEDIATELY. AS I TRANSITIONED ZZZ1 AIRSPACE; I WAS TOLD TO CONTACT TRACON BY PHONE; 'WHEN I GET A CHANCE.' UPON LNDG; I TURNED ON MY TRUCK RADIO AND LEARNED THAT A BASEBALL GAME WAS INDEED GOING TO START AT XB05. THROUGHOUT THE SUMMER WHEN I HAD CHKED FOR NOTAMS; SPORTING EVENT TFR'S HAD NOT BEEN INCLUDED. IN ADDITION; ALTHOUGH I HAD PREVIOUSLY BEEN ISSUED A WAIVER TO FLY INSIDE THE TFR'S; IT WAS LATER WITHDRAWN AS TO ALL BANNER TOWERS. REISSUING THE WAIVERS TO BANNER TOWERS WOULD RESOLVE THIS PROB. BROADCASTING TFR NOTAMS ON ATIS AND AT FSS'S IN THE AREA WOULD ALSO BE HELPFUL.