@Robert ******
The O-A retirement visa which you receive in your home country can definitely be automatically extended by another year by simply leaving Thailand, just before the visa expires and re-entering Thailand. They will stamp your passport at the airport for one more year. giving you 2 years on that O-A visa. That I am 100 % certain of. You may be correct that everyone with a retirement visa will need health insurance. BIG money involved there.
*****
retirement visa's issued last year in Thailand. If we assume that it costs each person
*****
baht per annum for health insurance, we are talking 2.4 billion Thai Baht involved here.