Attempting to warm migrate a VM with a virtual compatibility mode dependent RDM disk fails, the plan fails "vm has pre-existing snapshots which are incompatible with warm migrations", this is a bit odd as the snapshot was created by the warm migration process itself, there was not snapshot before. 

MTV 2.10
OCP 4.19

First time hitting this

1. Create a VM with two disks, OS is vmdk, second disk is a virtual compatibility dependent RDM disk. 
2. Create a warm migration plan with the VM
3. Start the migration, it fails with error: "VM has pre-existing snapshots which are incompatible with warm migration. To troubleshoot, check the Forklift controller pod logs."

Migration fails due to existing snapshot, I suspect the migration process itself created it due to it's name and time.

Well a cold RDM migration worked, a warm VMDK migration worked, we figured this may work without needing any fixes.