Hi Ray, can you confirm that this feature is now released with Odoo 16.0? I can't find info on it in the documentation yet.

I can. If you have access to the Enterprise repository, you can see the commit at https://github.com/odoo/enterprise/commit/752de890931031611ad21419424be2a88d6ae13b and if you can't, the Task description is "The current heuristic for Purchase Order matching on Vendor Bills leads to situations where there is a lot of work left to do by the accountant in case of incomplete matches between what's found in the scanned PDF and the linked Purchase Order. The objective of this task is to get to a situation where, when possible, a maximal amount of information found in an matched Purchase Order is taken by default in the newly created bill. It is often less work for an accountant to remove lines that come from a linked PO that were not present in the bill, than letting him have to reencode ignored lines from the document." I have also updated my answer to include an image of the matching logic from the Task in our system.