Hello,
Don't worry, it's a false positive.
Sometimes, you can have it too for plugin system.
iCagenda is a package with one update server.
But Joomla, even if it was improved since the first version, was not managing well extensions included and updated with a single package.
Now, only libraries and plugin system could have this warning (before last version of J3, it was all plugins and modules included in a package).
So, you can go for upgrade!
just what is strange: having two versions of iC Library.
This should not happen, but it may be related to a past bug in Joomla.
So, you may be able to uninstall older version.
(if both are removed, install again full iCagenda package).
Best regards,
Cyril
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