To Clarify Betas as Default vs Non-beta.

Right. Plus with Beta's and Alphas (as sometimes called) they sometimes continue in public beta even after the stable version is release. Meaning the public beta testing doesn't always just end, and that's it as some stable software/apps are always being updated itself. Once Edge stable is released it'll be updated/improved every few weeks or months or whenever they opt to do it as all other stable browsers do. I'm a beta insider for Edge for Android. I get the beta versions when they're release to the Google Play Store.  (If you go to the Google Play store, search and click for Edge, and scroll down more towards the bottom you might see an option that say's "Join Beta" in which case if you do you'll get the stable release and the in-between beta releases of Android Edge).  I've been using Google Chrome Canary for years as a secondary browser and Google Chrome has since 2011 the same Canary, Developer, Beta, Stable options as Edge does. Firefox has Firefox Nightly (their version of Canary) and Firefox Beta (their version of Developer since Firefox Aurora was discontinued) on top of Stable. I sometimes refer to Canary as "the beta of the beta of the beta" hehe.  

I don't know when Edge will be released into stable. The Beta channel hasn't yet been released and that alone states after the Beta Channel (Beta Version) is released it will be updated every six weeks.