Well done. If you thought that was easy you'll find doing the yearly extension even easier. For a start you won't have to go through the process of proving your address again because the info is now on the computer system.
it depends on the office. For Udon Thani it's 7 days. I was told by immigration they don't insist on the same day because there are a couple of banks that can't guarantee to get the letter to you on the same day.
I recently got my one year extension and I think it took about 20 minutes. That was in Udon Thani but the previous year I had it done in Phuket and I had to come back the following day to pick up my passport with the visa.
is there really a desk at the end that does that? Have you ever used it? I really don't blame the IO. He's only looking for the entry stamp so he can stamp him out. That's his only job, not to make sure every traveler knows every rule about immigration otherwise no one would catch their flights. It would take too long. He's not concerned about whether he's coming back or not as far as he's concerned he might be leaving Thailand for good. it's up to the traveler to make sure he understands all the visa rules.
That is correct, the Visa is canceled without a re-entry permit. If you anticipate leaving the country it's always best to get a multiple re-entry permit at the time you get the Ed Visa or any other kind of long stay Visa.
that's a good point. Better to come in on a 45-day exemption and then apply for a non-O and then convert that to retirement extension. Health insurance is not required. That's what I did.
if the passport you are using to get your extension has more than 12 months validity then you will get a 12-month extension but if it has less than 12 months they will give you the amount that is left on your passport. They only care about the passport you turn up with at their office. When you get a new passport you will have to go to immigration to get your visa stamp transferred to the new passport but you won't get a new extension at that point until the old one runs out.