As a GreenHopper user I would like the Global Rank to be the ranking field used in the Classic Mode

Big Story, Let's Break It Down!

COS:

• Automatically migrate the GreenHopper Rank field in an instance with only one GreenHopper Rank field to the Global Rank, take projects in alphabetical order and then the rank within the project over to the Global Rank
• Make the Global Rank the rank field that is used in the Classic Mode, switch all projects and contexts to Global Rank
• If there are multiple GreenHopper Rank fields then do not run the auto-upgrade task, lock GreenHopper until an admin selects which GreenHopper Rank field to migrate to the Global Rank (we will make a note of this in the Upgrade Guide too), once they have migrated move the other GreenHopper Rank fields to a Number Custom Field with a locked absolute rank per project for historical purposes
• If the Global Rank is enabled and in use we use the same approach where they have multiple GreenHopper Rank
• Do not remove the GreenHopper Rank field yet
• Give them a way to back out by downgrading GreenHopper to 5.7.2, which is okay before we have not performed any upgrade tasks