Bob Rivers, via BobRivers.com.On Dec. 26, after years of bouncing around different formats and temporarily spinning Christmas hits, KJR 95.7 reverted to “oldies.” The next day, KWJZ 98.9 switched to “Modern Music” after two decades of smooth jazz. Today, KJR’s parent, Clear Channel, announced that The Bob Rivers Show–most recently at KZOK 102.5–will become the station’s new morning show. Add these to the changes in the works at other stations in town, and we’ve got a serious local radio shakeup on our hands.Clear Channel says Rivers will start broadcasting on KJR on April 1, and that Rivers will be joined by his sidekicks, Spike O’Neill and “Downtown” Joe Bryant. Before his tenure at KZOK, Rivers’ hosted Bob Rivers’ Twisted Radio on KISW 99.9 for a decade.So there, Seattle, you’ve not only got your oldies back, but you’ve got your Bob Rivers show too. More returns and changes are expected to be announced in the coming weeks.