doc-pagebreak has this example:

<span id="pg04" role="doc-pagebreak" title="4"/>

along with "Accessible Name Required" of True.

I would hope that authors would combine the two pieces of information and conclude something like "Authors SHOULD provide an end-user-consumable page number as the name of the pagebreak." That way, a screen reader could include the page number information when the page changes and/or in a "where am I?" command.

As it stands right now, however, the name could be anything. And I've seen authors do strange things over the years.... 🤷‍♀️