Yup, that's a thing now with auditors. The :2019 version was harmonized (although apparently without the Z annexes and so it sounds like an update to the harmonized version is in works) so it's considered state of the art. You need to at least have a plan for transitioning to the :2019 version. (Side note: we showed the auditor that we recognized the update was made, knew that an additional update was pending, and said we'd make the updates then. She accepted that.)
This would be a document of external organization (which you should have) determined ... to be necessary for the planning and operation of the QMS (13485 4.2.4).
Presumably, you know of / have a list of all such external documents to which your devices comply. You need to monitor those to determine if updates are released (and if they're harmonized) and if they are updated, how it impacts you.