@Dan ******
If you happen to be at a land border you can ask yourself.
At certain land borders, they post the actual rules...but most are related to rules on visa exempt bounces.
One border, namely Chiang Khong, has a very interesting list of requirements for DTV bouncers...however, I assume these rules apply only to 1) actual same day bouncers and 2) particularly those who have a history of maxing out or almost maxing out their stays.