@Len ****
Yes. That's already different. I understand that this rule about 150 days without proper visa , only visa exemption (!) it's not even new! But, before, as in many other cases, the officials didn't really care about it. In fact, for about 2 years ago I was also able to get full extension by just leaving Thailand an coming back. Again, only with visa exemption.
Looks like right now , for some reason, they are reinforcing the law properly.