No updates to share just yet, @johanm, nor a concrete timeline for this at the moment. You can check out our roadmap to see what’s coming by the end of this year (marked as Started ) and what we’ll be working on next (Planned).
This does seem to be a relatively simple bug fix: if the Paperpile ref includes a page number, include that in the optional field in \cite.
And it is a bug (now present for several years). There is the option to export with BibTeX references – and it is not exporting correctly. This isn’t a feature request.