If you are looking for nodes that have been set to be unmanaged starting in the future, you can use this:
SELECT CAPTION AS 'DEVICE', IP_ADDRESS AS 'IP ADDRESS', UNMANAGEFROM AS 'BEGIN UNMANAGE', UNMANAGEUNTIL AS 'END UNMANAGE' FROM NODES WHERE UNMANAGEFROM > (GETDATE())
If you are trying to use SQL to set devices to be unmanaged in the future, that will be different.
- ZackM