I'd have thought that, as long as your funds are obtained honestly, then who reports what to whom is secondary to where you are resident to pay tax on your income. I've been non-resident for tax in the UK for over 20 years and HMRC shows not the slightest interest in my money offshore. They do, however, want their slice of my UK pensions, and that's fair enough since they gave me a decent tax break when I invested in them (except the state pension, but that's just a Ponzi scheme). The banks in the UK and offshore know that i live in Thailand and have my TIN, so the information is available to the TRD if they ask for it and, as I'm currently tax-resident here they can assess it for their share. If, however, I was to stay here for less than 180 days in a year like the OP then I'd be non-resident for Thai tax and whatever data was reported to the TRD via CRS wouldn't matter, as I would not be liable for Thai tax.