Original sentence: Instead, on or before June 12, 2009, which is the end of the digital TV conversion period for full-service stations, KUTH was required to turn off its analog signal and turn on its digital signal (called a "flash-cut").KUTH shut down its analog transmitter on June 12 and turned on its digital signal on channel 32 the next day
Edited sentence: Instead, on June 12, 2009, which was the end of the digital TV conversion period for full-service stations, KUTH turned off its analog signal and turned on its digital signal (called a "flash-cut").KUTH officially shut down its analog transmitter on June 12 and turned on its digital signal on channel 32 the next day