Once we have created a release and scoped all the items into it, it would be helpful if we could "soft lock" the features in that release. A soft lock could be an option on each release with a toggle and a message. Once the toggle is ON and a new feature is attempting to be added to that release, the message appears. The feature can still be added on clicking OK to the message.
An example of the text might be "The scope of this release was agreed on the xx/xx/xxx - please raise a change request before adding this feature"
Currently contributors and product owners can move items into existing releases, while reviewers and viewers do not have these permissions. Leveraging user roles and permissions is one way to "lock" releases so that some users cannot make changes. Another potential workaround is to enforce this offline that once a release has been set to a certain status, that users are no longer allowed to add new features.
At this time, we do not have plans to make changes to the user permissions model based on feedback from the community and current priorities. We hope you can understand.