The easiest case is when the issue is marked as Fixed, indiciating that the fix has already been tested and applied to the live server.

A fix for the issue marked as Need update may have or may have not been applied. You can easily find out if you are an Authorized User.

You can use the [Switch Stats] button in the page header to switch the realm statuses and the last update dates. Now you just have to compare the time of Last Update with the time when the status Need update was set in the issue's tab Status Changes.

Now you just have to check if a server restart has already taken place (item Last Restart), which would run the updated version of the core.