Litigation Hold Mailbox Migration

My company is currently moving from Exchange 2016 to 365. We are currently setup in a hybrid environment. The question arose of how do we migrate mailboxes that are on litigation hold.

I have found that you can do a migration of the lit hold mailboxes from on-prem to 365 without any issues per this document - https://learn.microsoft.com/en-us/exchange/policy-and-compliance/holds/holds?view=exchserver-2016#migrating-mailboxes-on-hold-from-exchange-server-to-microsoft-365-or-office-365. However, what I can't seem to find is the best way to test a migration for a lit hold mailbox. I also have found that some of our lit hold mailboxes have been on hold so long that their mailboxes are on Exchange version 0.10.

So, I really have 2 questions.

1) How can I test migrating a lit hold mailbox from on prem to 365 without using an active person's mailbox?

2) Does the Exchange Version for the mailbox matter when I migrate them?

Any help would be much appreciated.