I haven't yet upgraded to 2.7 but plan to in the next (working) day or so. When upgrading to a new version of ArcGIS Pro, if you have cloned environment that the previous version pointed to, that environment is no longer available to your newest version. This is one of the reasons I'm always hesitant to upgrade. Seems like I get an environment just the way I want it with additional packages and ArcGis Pro gets version change. Incremental upgrades (2.6 to 2.6.1) will honor the current, active clone.
That should just about do it....