Another great feature introduced in 2.8 is the ability to lock note changes in addition to metric value changes after a certain amount of time. Both of these are set per calendar in the Administration section. Just like the ability to edit values, notes will always be editable by application administrators.
We've also added the ability to block scorecard object metadata (name, equation, etc) and structure editing after being archived. This is a global configuration option in the Admin | Application Administration screen. Application administrators will always be able to update structure, even when this restriction is on place.