Disclaimer: This is a very touchy-feely subject for most authors who have been around for a while, so excuse the harsh tone.


TL;DR: No update means the addon is still working*. Stop bothering the author, enable "Allow out of date add-ons" and be done**.

If you felt the need to ask this question you are obviously not very well informed in how addons in Elder Scrolls Online work. The "out of date" check in the game holds no real meaning and simply compares a number in a file inside the addon to a number stored in the game client. When those two numbers do not match, it will be marked as out of date and by default the game will not allow you to enable the addon. This is done without any regard for the actual state of the addon and as such it will 99.9% of the time still work without an update.

In order to get the addon to load again, there is a checkbox in the addon menu "Allow out of date add-ons", which will disable this useless check and let the game act as if the numbers were equal. Unfortunately as ZOS is quite sadistic at times, they choose that it's not enough to just have this annoying system in place, in addition they also decided it's necessary to automatically uncheck the allow out of date checkbox on every major update, so hapless users are confused once more when they first encounter that. Simply re-enable it in that case and you are set for the next few months.

* as long as the author is still active

** unless you found a real problem after you re-enabled it