There is no 60-day visa on arrival. There is a 60-day visa you apply for ahead of time and a visa-exempt (no visa) stamp you get in your passport when you arrive.
It doesn’t matter. Volunteers need a work permit. Seriously. However, Immigration doesn’t look for infractions unless someone reports you. Then, they are obligated to investigate.
Not sure any one person has experience with all 223 Immigration offices. Besides, the policies probably change from time to time, maybe as each new manager takes over or changes their mind.
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