180 days:As far as I know, the rules are the same as for everyone else. You are only considered tax resident if you spend 183+ days per calendar year in Thailand.
Tax residents pay tax on their global income now. But if you spend less than 183 days there, no tax.
https://taxsummaries.pwc.com/thailand/individual/residence
Also observe the PE rules, your company may be deemed having a PE earlier.