What is the process for extending an O-A Visa in Thailand, and what new requirements should I be aware of?

Today we made extension based on O-A Visa in Jomtien.

My extension is based on 800 K, my wife got dependent Visaextension . No money required.

The officer was very friendly, not many people, it takes us 40 min to do all.

In the end i got a paper that says i must show my updated Bankbook in 3 months. My money is there since 4 years inkluding the interest,......- no problem.

But it was the first time that they want to see the Bankbook after 3 months. So this is new.