I will be flying out within 7 days after my 3 months since I arrived. So within 91-96 days after arrival.

Will that be accepted, or does the 7 days after only accepted at immigration office where I belong? Would save me for a roundtrip of more than 3 hours extra the day before we leaving for Bangkok in the wrong direction.

The 7 days is for late reporting, not missed reporting. However it won't make any difference to you leaving or returning, only potentially when you do your first report and a super-keen IO spots it.

10 minutes ago, Upnotover said:

The 7 days is for late reporting, not missed reporting. However it won't make any difference to you leaving or returning, only potentially when you do your first report and a super-keen IO spots it.

I haven't reported online for a year or so, and been flying in and out a few times since last 90 day report, can I do my first report online, or do I need to do it in office. Can't really remember how it was after being out and back in again?

Just now, Hummin said:

I haven't reported online for a year or so, and been flying in and out a few times since last 90 day report, can I do my first report online, or do I need to do it in office. Can't really remember how it was after being out and back in again?

First report after returning has to be done in person, or potentiality by mail, but not online.

Officers and offices can and do vary.

Generally, as I understand it, the first report has to be done in the office in person, subsequent can be done online, 15 days prior upto 7 days prior, the 7 days after ONLY app;lies for late reporting at the office NOT online.

AFAIK

OP, you have correct answers above.

If you are currently still 15 days prior to due date you could do the report using mail option.

Personally I wouldn't opt for the 3 hr round trip to do it in person.

There is a good chance it wouldn't even be noticed for next report after your return to Thailand.

In any event at max you would be up for 2k fine.