Mac updates are a total replacement of the application so the first (and subsequent) updates totally replace what was on the CD. If you want a backup, I suggest that you just copy the Applications Folder -> TurboTax...2016.app to a flash drive, new CD, backup Hard Drive or where ever you want it. You can restore just by dragging it back to the Applications Folder if you need to. Then it will contain all updates up to the time that saved it.
Note: If you have a state download, that will not back up the state since the state is stored in an Applications Support folder in your users Library and is not part of the application.
**Disclaimer: This post is for discussion purposes only and is NOT tax advice. The author takes no responsibility for the accuracy of any information in this post.**
