you don't renew your retirement visa - you renew your permission to stay. That's why it is called extension of stay. Always ask your local immi for their folder where they describe the requirements since they can differ (slightly) from immi to immi.
always ask your local immi for the folder they have for their requirements because they are not all the same from immi to immi. And your non-o was an entry permission and was basically used when you entered and replaced with a permission to stay - the length of which is based on the visa type.