Why do you not get your pension paid into your own personal bank account, so then you can transfer to your Thai Bank, be it via Wise or Swift or other way. YOU then decide which day of the month it transfers.
As an off topic aside, isn't it strange that I can do a transfer from my current account to any other account in UK at any time of the month, day or hour and it is almost instantaneous. The computers DO NOT go to sleep.