The FAQs says:

WHERE CAN I FIND PRIORITY DATA FOR EVERY PATENT?

Priority data can be found in multiple locations depending on the nature of the priority and patent grant date. Foreign priority data is available in the foreign_priority table of the PatentsView database. U.S. priority data can be derived from the related applications data available in two tables: rel_app_text and usreldoc (all tables can be found on the bulk downloads page). We recommend combining information from both tables since each covers different time periods. For example, the source data for patents granted 1976-2001 contains only textual references to related applications and other related documents. Source data for patents granted after 2005 provides more structured information.

However, rel_app_text and usreldoc do not appear to be accessible using the Patents Endpoint query system.  This page (https://www.patentsview.org/api/patent.html) does not list these two fields, as they seem to only be valid for bulk download.

Is there a way (using this API or other API) to access the US priority information (serial #, date, relationship (e.g., CON, DIV)) for a patent or application?  The US priority information seems to be much more relevant than many of the other fields currently supported.  If it can be accessed via a query, can you please provide guidance on how?

Thanks in advance!