You don’t need to wait until your 50 years, but you’ll need to prove £ 9,300 to apply and two months each year prior to your yearly application for extension of stay.
Some immigrations accept proof of a monthly income of minimum £ 930 for your yearly extension of stay.
That’s the requirement for apply for a Non O visa based on marriage and yearly extension of stay in Thailand.
If you apply for the Non O visa at the embassy before you leave, this is the requirement at the Thai embassy in London.
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