On the Hyper-V host, execute the VSSHP "stxvquery (Backup status lookup command)" to check the copy status. If any copying is in progress, use the VSSHP "backup control command (stxvcopy)" to stop copying.
On the Hyper-V host, perform "8.2.3.2.6 Creating Copy Set File" and "8.2.3.2.7 Registering Copy Sets as Batch" to change the copy type. Then perform the tasks described in "8.2.3.2.8 Checking and Saving Copy Set Registration Contents".