Commit plan to database

With the absence of an undo button many of our users have complained of getting in a mess and spending a lot of time trying to undo what they have done when updating a plan. One suggestions was to have a mode where the plan is locked and only editable by the person who locked the plan. At this stage edits can be made but are not committed to the database. If the edits are deemed successful then the user can commit them to the database and unlock the plan.

This is a bit analogous to time sheet entry where times can be entered and changed as you go through the week but won't get committed until the Submit button is pressed.