Handling this is a bit tricky, the easiest way to do it is to hard code the check. However, we always have to remember that the user may not have an assigned state, it may be replaced by queued, or in-progress, or whatever. The aim at the moment is to avoid having special handling for specific statuses, but there is still a lot of work in this area.

In my opinion, the cleanest way to fix this problem is through the user of plug-ins. This is to have a plug-in function that can be given a bug old and new information and it can decide whether the change is valid or not. The advantage of plug-ins is that the user can define user-specific logic based on the user-specific statuses.