If you change the release of the project we currently don't check to see if the machine set is still valid.
Clearing 2.0 milestone
We could remove the capability to change the release for a project, so it's frozen when you create the project. If you want a project for other releases, make a new project. This would considerably simplify things.
How do we know if the machine is valid or not? Do you mean if it is still provided by one of the layers in the project after the release change? About Elliot's suggestion of not being able to change the release, that is a bit draconian, particularly because we don't have an easy way to delete projects right now. What if I selected the wrong release by mistake? (which, by the way, just happened to me yesterday) I rather keep the ability to change the project release, if at all possible.
We no longer allow users to change the project release, so this should now obsolete.