After attempting an online 90 day report on a non-o based on marriage visa extension and failing, went to report yesterday at Chaeng Watthana.
Made the mistake of thinking the 90 days started from my visa extension stamp date not the date I entered Thailand so was about 75 days overdue and hit with a 2000 baht fine (staff where really friendly I might add and told me that the online report should work next time if I do it at the correct time, I thought I might get some grief but no problems at all)
No mention of the TM.30 though.
So just a reminder that doing an extension doesn't necessarily reset the 90 day clock...
Not sure if helpful to anyone or not but thought i'd post my experience.. 👍