I updated the installer with a bug fix so that it would recognize preview releases and now it takes them by default.

I noticed that yum update now takes subsequent preview releases - but I'm uncertain whether that is because I already took a preview or if the yum repository is serving up the latest regardless of preview status.

As a consumer of both the installer-powershell.sh script and the Microsoft Linux repositories, I think opting into previews should be under the control of the installer and default to stable only.

I can foresee how that would mean a special switch on install-powershell.sh should be necessary, but I don't know if the repository is setup properly to serve only stable by default?