The migration will have impact on the control plane operations (i.e. they won't be available during migration). It should not affect data plane operations (e.g. network traffic between VMs on the VNet).
You cannot revert once you commit the migration.
This does work as intended as long as you satisfy the prerequisites.
If the above response helps answer your question, remember to "Accept Answer" so that others in the community facing similar issues can easily find the solution. Your contribution is highly appreciated.
hth
Marcin