If you upgrade all the time you may find that you are missing licenses.
As I recall SecureXL was such feature that was silently added but was missing for some customers because they upgraded from pre SecureXL times.
This is something to keep in the back of your head when you upgrade customers that have been upgrading licenses for many years.
It's usually something you can discuss with your SE and something can be arranged to remedy the issue but it's more a sales type of issue.
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