I have a similar problem. I still have the old app on my iMac but the 80 app on my iPad. Most of my stations have disappeared on the upgrade while I can still play them on the iMac which wasn’t upgraded. If I do a search for a Sonos radio station, there are some I can’t save in the 80 app upgrade. It’s a confusing mess. I now have only about 10 stations I’m able to listen to on the 80 upgrade. However I can listen to all my old stations on the old app on my iMac. It’s all very frustrating.