How do I cancel an O-A visa in Thailand?

@Geoff ******

and this topic is about to be closed as well.

I would imagine when you go back to the UK in Dec-Jan you will have an idea of what is happening insurance-wise on the O-A visa situation.

THEN you can contact the consulate that issued the visa, see about getting a NEW 90 day Non-O visa from them AND see about canceling your current O-A.

Again, I think you're WAY ahead of the game on this and suggest one final time to WAIT and see what's actually going to happen..

if he is already in the second year of his O/A, he just needs to do a border run without a re-entry permit, in order to void the visa. As a U.S. citizen, he will be given a 30 day visa exempt upon re-entry and his existing Non-Imm-O/A will be stamped VOID

I DID answer you. I said I do NOT know how you cancel an existing VISA that is still valid.