There was a petition to deny filed by Common Cause in May. That was before the radio deal was announced, but it includes radio in the Dayton market:
https://ecfsapi.fcc.gov/file/1051143903250/CC CCOH UCC Apollo Cox Petition to Deny FINAL 5-10-19.pdf
https://ecfsapi.fcc.gov/file/1051143903250/CC CCOH UCC Apollo Cox Petition to Deny FINAL 5-10-19.pdf