What a breeze, I've just been to Chaengwattana to extend my non-Imm O for being over 50 and used the appointment booking system for the first time.
My appointment was for 9.45, I arrived at CW at about 8.45, had a leisurely coffee and updated my bank book and got an updated xerox with today's date, went for my appointment early, about 9.20, went directly to L zone, let them know that I was there, at counter 33, was seen at 9.30 and was walking out of the building at 10.00, with passport and new year's stamp included.
I can definitely recommend using the booking system, zone L was heaving but I didn't need to worry, I sailed through.
I used the document check list and forms from files in this group.
Booking for Bangkok
TLDR : Answer Summary
The author successfully extended their Non-Immigrant O visa at Chaengwattana using the appointment booking system, highlighting the efficiency of the process. They arrived early, enjoyed a coffee, and utilized a document checklist, allowing them to complete their appointment swiftly, receiving their new visa stamp in about 30 minutes.
