Accounts & Subaccounts & Sub-subaccounts, oh my! 

My institution has an established set of subaccounts within the root account that we have worked within for the past five years. We have been expanding recently and are now investigating potentially revising our hierarchical account structure. We would like to be able to move an existing subaccount to nest it within a mid-level subaccount in order to help manage admin permissions, reporting, etc. I know we can create new subaccounts and we can delete subaccounts after moving courses out of those subaccounts, but that sounds like a round-about way of achieving this goal. 

For example:

Here would be a model of our existing structure:

• Root Account
  • Subaccount 1
  • Subaccount 2
  • Subaccount 3
  • Subaccount 4

Here is a model of what we would like to move to:

• Root Account
  
  • New Subaccount A
    • Subaccount 1
    • Subaccount 2
  • New Subaccount B
    • Subaccount 3
    • Subaccount 4

My questions are:

1. Is it possible to move a subaccount to nest it into another subaccount? (If so, how?)
2. I'm assuming that, if this is possible, it would not impact courses (live or concluded) that live within those subaccounts. Am I correct in that assumption? If not, what should I be wary of?
3. Is there something I'm not thinking of that you would urge me to consider? 

Thank you very much for your help!