Update Open PO via REST API

Is there a REST API that will allow us to edit POs that are in 'Open' status (already communicated to supplier)?

For PO header changes: Update comments

For PO line changes: Update quantity, comments, promised delivery date, and unit price

Not able to find any REST API documentation surrounding making changes on a PO that's already been communicated, aside from canceling or closing.

Thanks,

Andrew