What does the stamp stating 'certification of residence must be made every 90 days' mean for my O-A visa extension?

The stamp indicating that 'certification of residence must be made every 90 days' refers to the normal reporting requirement for foreign residents in Thailand, commonly known as the 90-day report. This report is necessary for those on visa extensions, including those related to retirement. It's crucial to note that this 90-day reporting period starts from your initial entry into Thailand, or from the date of your last 90-day report, not from the date of your visa extension. Therefore, you should ensure to adhere to these reporting requirements based on the dates outlined in your visa documentation.