Hi there,
At this point in time as you have noted, VMware don't support a parallel migration from windows VC to the VCSA. This is something that they appear to have received a lot of feedback on and are likely working on, but of course won't commit to a release date for such a utility.
So at this point in time your option is to stand up a new VCSA based deployment and then migrate hosts, VMs, roles, permissions, plugins etc across to the new vCenter Server. There is no way to bring across the database itself, so during this type of migration you will lose some statistics such as historical data.
Cheers, Matt.
VCP6-DCV | VCAP6-DCV Deploy
@mattallford
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