Is a license needed for an Inactive mailbox

Hi All,

We are working on a new out of service procedure for users.

We want to use litigation hold to save a user's mailbox.

We know that to put the mailbox on litigation hold u need at least a exchange online e2 license.

But still we cant find a definite answer that after you put litigation hold on the users mailbox you can safely delete the license.

https://docs.microsoft.com/en-us/microsoft-365/admin/add-users/remove-former-employee?view=o365-worldwide#remove-and-delete-the-microsoft-365-license-from-a-former-employee

as you can read up here, it still says that after deletion of the license the data is only retained foor 30 days.

Can someone confirm that you don't need an active license when a users mailbox is put on litigation hold and the users account is deleted (mailbox is set to inactive)?