My O-A visa expired back in 2006 and I've been doing annual extensions based on retirement ever since
I don't really see the relevance of initially having an O-A visa, rather than a non-O. Once the visa has expired you just do the same extension thereafter for either type.
I also don't see the relevance of differentiating between retirement and marriage extensions - if they do so. Are there no married foreigners here that are over 50 years of age?
As usual, clear as mud and I suppose that all we can do is wait until the murk clears - and maybe formulate 'Plan B' in the meantime.
I'm 75 in December and have health issues. Previous medical treatment I have paid for myself as I can't get insurance. If this new insurance requirement is enforced for retirement extensions then that will be the end of the road for me and, I suspect, many others. The prospect of repatriating to UK does not exactly fill me with joy but if it has to happen then so be it.