To teach mandarin in Thailand ?

I am hoping to find a teaching job in Thailand in 2-3 years time, teaching mandarin--my mother tougue.

I have been living in the U.K. for the past 17 years. I have British passport and gained a degree in politics in an U.K. University many years ago.

I have been teaching mandarin in a weekend Chinese school for some time now, and also studying an online course to become a mandarin teacher, the qualification is very similar to TEFL which called TCFL.

After I finish my Chinese course, I am planning to do a part time level 3 college course to be trained as a teaching assistant to gain some classroom experience.  Hopefully I can find a school to work for or even voltunteering. 

There seem to have a demand of mandarin teachers in Thailand that speaks good English , especially  in international schools. 

Does language teacher has to have a PGCE To teach ? 

I have two school age kids, it will be very hard for me to study a demanding postgraduate course while living a family life. 

Anyone has experience please give me some insight!

Thanks!