A standard MX send does not have version control; the data is sent in a unique transaction number and it is read-only at the point of upload.

A Distribution however has version control and you can also modify (add or remove) recipients of the data over time. The latest version of the data is always the version that users can get to, even if they go to an old email.

You would need to speak to an Administrator for your account, to see if they have Distributions as part of their package and to create the initial Distribution for you to work with.

See below on how to view the full list of Administrators.
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