I will arrive in Chiang Mai from the US on 2Nov and depart on 1Dec for which I was counting on a 30 day stamp on arrival. It just dawned on me that this will be counted as 31 days. It seems at this point my simplest solution will be to visit another country for a couple day side trip. Agree?
TLDR : Answer Summary
The user is unsure whether their arrival on November 2nd and departure on December 1st will exceed the 30-day stamp they expected to receive. They consider a trip to another country to reset their visa, while commenters clarify that their stay will actually be within the 30-day limit and suggest they could extend their visa at an immigration office.