To know if Smode is a beta,
Just check the branch name,
If the branch name is not a Number like 8.3 or 8.4... but a text like "master", it is a special non public version of Smode
The Smode Versionning form is MM.mm.ccc.sha (8.4.38.2d9c426d64)
MM: 8 is the Major version, huge change: Licensing, major features set and possible breaking changes...
mm: 4 is the minor version, small change, new features but no fundamental rewriting.
ccc: 38 is the number of changes and fixes since the last minor version is out.
2d9c426d64 is a unique identifier for developement purpose allowing to know the date of release and many other details.
A good hint to know if a build is a beta is a big ccc number (842): Near to the next 8.5 release. (like 8.4.842)
You can manually download all versions kind on the usual download web site (sent from a separate email)
Hopping all of this can helps.