I don't know where you are in Thailand but in Phuket ( central shopping, ground floor ) you can just show up and every time i went, no queue Very friendly and helpful
I had my "2 years" only 1 year and needed an international .. they cannot give international on a 2 year, so they changed that first ( after or in the first year ) to a 5 year and gave me then also the international
That was in Phuket in 2019 ( will expire soon ) I don't know if I was lucky but they did it at the official office so it's possible, if they want ..