Yesterday I noticed the nice cover art display on the lock screen of my upgraded iPhone. Today while working out I noticed it was working differently, much closer to the old style.
I couldn’t think of what might have caused the change. I scrolled up and there were some older notifications. I deleted all of them, but still no change. Then it occurred to me to tap the thumbnail of the cover art.
I have no idea why it was defaulting to the thumbnail today after defaulting to full screen yesterday.