Apple Music seems always assumes you have good network connectivity. There was one year I upgraded my phone's iOS at work (probably 2016 or 2017), when heading

Apple Music seems always assumes you have good network connectivity. There was one year I upgraded my phone's iOS at work (probably 2016 or 2017), when heading home that night, the Music app no longer loads but a blank screen, even I have all the iTunes music on device locally. Later I found that first load of that upgraded Music app has an Apple Music pop up for "free trial", that requires data connection, which my company's garage happen to be a cellular dead spot. Before you dismiss that offer, you cannot even use the Music app.