Tone chapters is the original question. Start, confirm you hear a tick once a second, lock the phone, wait two minutes, wake it. If shortfall is still under a couple of seconds it never stopped. Every lock-screen and Bluetooth button you press should appear in the log.
Whole book is the new one, and it is only answered over Bluetooth with the screen locked. It loads one real book from one URL, once — watch src writes stay at 1 all night — and renames the chapter in the notification from a timer as the stream crosses each boundary. What has to be looked at, because no log can see it: does the panel keep the same session across a rename, or does it blink out and come back? Then use Seek to the middle for the morning resume, and turn the tailnet off for half a minute to find out whether the phone still holds the book.