@Jona****
the seasoning for the banked money for a yearly extension based on marriage to a thai is TWO months BEFORE you apply for the extension (not 2 months before your current extension expires)
There technically is NO seasoning for the 400K baht banked money for raising half thai children (as in there is none listed in the police order).
You can apply for a new extension right up until the day you current one expires (although I wouldn't wait that long in case you are a document short or something)