@Robert ******

Thank you. I am very clear about the end date for my OA Visa and would go to Vientiane and stay 1 or 2 nights. A RT flight from Chiang Mai to Nong Kkai is half the cost of a flight from Chiang Mai to Vientiane, plus I will probably visit someone in Udon Thani.

I'm going to add this question to this thread, as it is directly related to the OP. When leaving Thailand and returning near the end of the first full year of the OA visa, to be able to get a 'permitted to stay" stamp of one more year, can that be done overland or must it be done via an airport? I imagine there's no difference thread, but I want to be sure as I may do this overland at Vientiane at the end of October.