Just got back from Nakhon Sawan immigration and 30th November stamp refused.
I had been on Amnesty since July previously had Thailand Elite visa. Eventually got my Embassy Letter requesting a Non O for retirement as a long stay resident of Thailand.
A processing stamp was put in my passport on 3rd September until 17th September.
Told to come back on 17th to get stamped in until 26th October which I did. New Amnesty announced that this stamp would get me until 30th November just need to go in and update at no charge.
Told today that is only if your on a processing stamp and need to go back before the current amnesty ends to get another 60 days until 30th December and no embassy letter will be required on this occasion.