Update: I took the paper from BOI/my company (stating my resignation / termination), passport, and a copy of the passport, to Chamchuri. They voided it without issues or fees. In and out in 15 minutes more or less.
If you mean the visa itself was at that time AN extension (from the original visa from years earlier) - then yes, I was at the time of employment on an extension, correct. But I am not sure what the relevance is compared to if I had been on the normal non-extended visa?
Thank you. Could you explain the extension part a bit more? My work officially ended, say March 1st, that's what the document says and that' what my employer said to be the official cancellation date, that's also when I left the country. The WP should be cancelled too (at least I can't log into the app anymore).
But in general - you're saying there is a chance I can just show up on Monday with that document and get it sorted? Fee or not, I'll take that hit if I have to.