Understood, thanks!

I more commonly see that "-beta" version-number suffix used as meaning, "this is a beta version of 0.8.1, the real 0.8.1 is coming later".  And, if "-beta" is considered part of the canonical version identifier, it would help to also include it in the announcement of availability, download file name, and Github branch name. (Even saying, "Beta-0.8.1", as a prefix rather than suffix, would help avoid conflict with common practice elsewhere.)

Tom Preston-Werner of Github has a nice attempt at formalizing the practices I'm most familiar with in his "Semantic Versioning" proposal:

http://semver.org/