Ok thanks for the advice, After my Non-O multi entry has ran out and I exited on the last day it’s finished 30th August can I go to CM immigration and extend for 60 days based on marriage to a Thai.
You can go to Mae sai no problems at all and cross it’s when you go to get a new visa that the problems occur which happened to me and it took 2 days to sort out at immigration so do everything by the book and it will make you life better in the long run , I also bought my letter to don Muang airport they took the letter but didn’t cancel it.
I also tried this once but getting to Thai schools to work together is impossible more or less in the end I had one day left to get out the country and the paperwork was not ready so I had to leave and start the whole thing again.