We have a beta release of some new functionality being rolled out and we want to only allow users within the beta to see the new features while at the same time we want to mute the users ability to see the old process. My assumption here was that I could create a "Beta Feature" Permission Set Group providing them with all required permissions for the new feature. Additionally I would add a muted permission set group and mute access to the process we're replacing.
The documentation examples I've seen give me confidence that I can remove users CRUD access to the object record type and fields, but the issue is when I mute the "custom permission" which is used by Flow and Lightning Page Layout to control the visibility of components. Although I have muted the custom permission the user still seems to have access to the old process.
Am I missing something or is it just not possible to mute custom permissions?