Although not Classic Rock, Cool 105.7 (KOKZ) in Waterloo, Iowa had been Oldies for awhile. Over the past couple of years however, they've transitioned to playing more from the 70s, 80s, and even 90s.
Clear Channel's two Classic Rock stations here in East Central Iowa, those being KCQQ-Q106.5 (Davenport-Quad Cities) and KKRQ-100.7 The FOX (Iowa City-Cedar Rapids) have been playing more and more Early and Mid 90s Alternative Rock since CC went to using a Satellite Fed format from the "Format Lab." Although they still play 70s and 80s Rock, they don't play much of anything from the 60s anymore, which they used to. The only thing I hear from the 60s is The Beatles and The Rolling Stones, maybe Bob Dylan once or twice a month.