If you are going to the local immigration office for 90-day report in person, the reporting window is from 15 days before until 7 days after the due date.
If you want to try to do it online, reporting window is from 15 days before until 7 days before the due date.
, documents you have to submit are different depending on the reason for your Non-O visa (retirement, marriage to a Thai, guardian, trailing spouse, etc). Please make your own post mentioning what your Non-O is based on.
Check your airline first. Some airlines accept passport valid for less than 6 months for boarding IF you have VALID visa (or proof of permitted to stay) in your passport. Easiest might be renew a passport as people said.
I'd apologise first for that I cannot say for sure.
I remember there was a report (tried to search, but couldn't find the exact one). This person had to get proof of source of income (pension) from his home country as his embassy doesn't issue an affidavit. He wanted to use monthly international transfers of 40K baht each for a yearly extension based on a spouse to a Thai. His immigration office asked for proof of source in the foreign country of his income to allow him to use international transfers for marriage extensions. Please note that not all immigration offices allow this (monthly international transfers) for marriage extensions.
Also, this is not the monthly income method by an embassy affidavit (you don't have to have a Thai bank account) OR for a yearly extension based on retirement.
Again, I cannot say for sure, but this MIGHT be worth checking what the local immigration office actually wants to see.
and members who are giving advices, please be aware there are differences of requirements and/or documents accepted depending the embassy you apply/applied for your visas.
Your information may or may not help without the information of the embassy.
Dear members, please not make a comment unless you are going to apply for your visa through the thai embassy in manila. also be aware there might be diferrences for different nationalities.