A. Yes, existing snapshots are fully supported. The only change to the process would be when the Hyper-V snapshot is taken for QSM purposes, the existing differencing disk would be closed and marked read-only. A new differencing disk is created for the changes made during the VM copy. The original VHD and AVHDs would all be copied and then the AVHD for the QSM purpose would be copied during the VM save state and merged into the most recent AVHD used in the snapshot. This means that after the storage migration, all the existing snapshots would still be available.

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