Bethany Seeger recently contacted me to ask about removing the word "master" from PreservationMasterFile in the PCDM Use ontology. I've opened a PR to deprecate that term and add PreservationFile to replace it. The PR's been approved and is on track to be merged on 4/17:
Please speak up here or on the PR if you have comments, or if this would pose any problems for your use of the ontology.
Given how little change there has been in these ontologies recently, I propose we leave the deprecated term in the ontology for a year, and remove it after that.
-Esmé