Muang Thong Thani extension update as at today 2nd of April.
I arrived at 4am just to see how quiet it would be and I was about number 10 waiting at the gate. Once it was opened at around 5am people literally ran to the waiting area and I ended up number 26. The requirements for the extension posted today are attached as well as an image of the STM.2 form that is the second requirement on the list.
The directions from the immigration website will take you to the wrong side of the complex on a dead end dirt road. The actual location of the gate is here:
[members only]
Waited in the first waiting area until about 6am then upstairs to level 2 until 8am when the next step opens up. I can try to update in replies once I have had my turn.