Interesting. thanks for sharing. you try a DNS block on it?  you're sure that the DNS call is coming from that app? what tool are you using? 

 Yes, DNS block works and the calls are registered from AntennaPod by #RethinkDNS 

 Could it be checking for a new version?  I suppose though F-droid would be doing that tho 

 Fdroid checking at https://secure-uk.imrworldwide.com/ ? No way