Given that some content that acquires the BVAS tag, has the tag due to the original post having file sizes or dimensions that exceed what e621 either can, or is willing to handle there is a good chunk of content under the BVAS which isn't able to be replaced with its best public version.
Thus I have a suggestion, and was wonder what others would think of making a new meta tag to put on these posts instead:
LEVAS: limit_exceeding_version_at_source
There is also the matter of content that despite having an accessible and archivable better version, there is restrictions on the content which also make archiving that better version, impossible. On this content I would suggest a tag to replace the BVAS with:
DNPBVAS: dnp_better_version_at_source
Updated