I am the designated DNS Directorate reviewer for draft-ietf-dnsop-zoneversion. The draft is well written and defines an EDNS option which can be used for debugging purposes.

In general I think the draft is ready for publication.

Nits:
During the WGLC there were a some discussions on the -02 version of the document to clarify a few details in wording. I have not seen any update to the document and it might be useful to check if those comments need to be addressed. 

The size of an "unsigned decimal integer" is not defined (see rfc6891).

It might be useful to extend some of the abbrevation if they are used the first time (e.g., meaning of RR, SOA, ... depends on context).