Sentak1996,
The beta version is already available on Steam. X-Plane / Laminar Research works closely with Steam as a partner for both sales and to support VR. Steam is required for VR in X-Plane regardless if you are using the Steam or non-Steam edition.
11.30 is only a Release Candidate right now and thus isn't a final release. You should see the update automatically install shortly after its release to the public. If you do not wish to wait you can opt-in to the beta access in Steam and it will immediately download and install 11.30 (11.0.30.12 is the current beta version on Steam. To opt-in to the Beta, you need to right click on the game in your library and go to properties. Then select the BETAS tab and use the pull down to switch from "NONE - Opt out of all beta programs" to "public_beta - Public Beta". It will give you the option to type in a beta access code which is not needed and should state you have successfully opted-in to the public beta. You can then choose Close and the game should be downloading the Beta edition of 11.30. Your software should now show in your library as "X-Plane 11 [public_beta]". To opt out you can simply do the reverse and select the NONE option but this will not roll back your software. It will simply only install finalized updates from that point. If you need to rollback you will need to uninstall and reinstall your game.
I hope this helps,
Scarab