Back from Phuket Immigration, I was a little afraid they would not accept the forms filled with computer typing, so I filled them with handwriting blue ink. But then I met some fellow expats same age and saw that they had filled the form in advance by typing it but the fonts have to be blue. So thats accepted.
You need 1. Bank letter to confirm the current money of 800k + 2. Bank statement from the past months since opening acc. or visa issued. 3. Updated bank book with a transaction made same day when applying extension and copies of of all pages from bank book as well.
Best is to go to immigration and get the detailed list of all needed documents for EoS based on non O visa. It could vary from province
Well in the meantime I got some more people in other forums who posted they received this Mail from Kasikorn. I also found some information here:
I think the most reasonable anwer there was, that most elder accounts receive this mail now and those opened shortly already signed thos forms at the account opening. This would at least explain why some got the mail and some not.