My approach checks if todays date is greater than or equal to the G cell date plus one year.
The other checks if the date in the G cell is less than todays date.

There is also no guarantee the other will execute, if the workbook was saved and closed with that particular sheet being the active sheet then the Sheet_Activate event does not trigger when the workbook is next opened, and if that's the only worksheet in the workbook it will never trigger, where as the Workbook_Open event triggers every time the workbook opens.