Should I transfer my retirement visa to my new passport now or wait until next month for renewal?

I am doubtful you're on any visa 😕 and sounds more likely you're on a yearly extension of stay based on retirement from an immigration office <- Look at the current stamp in your passport.

Many people routinely wait until their next 90 day report OR their next extension comes due before they go to the immigration office to get their extension stamps moved from the old to new passport, so you can wait until you go apply for a new yearly extension and do it then.

Make sure you file a new TM30 with the new passport number as well (and don't forget to update your banking info at your banks)