Just go in on the due day and apply for it and when they tell you that you need the bank statement plead ignorance and they will tell u to go and obtain it keeping your application pending. Then go back and tell them it will arrive tomorrow. They might then charge you one day overstay of 500thb which is what my immigration office charged me with my 1st O retirement extension because my 800k thb was one day short of the 2 mths seasoning when my 90 day O visa expired. Or go in ASAP and explain your situation and see what they suggest.

Thanks for your replies.

Not a through booking but strangely the same airline Vietjet who only offer the flights separately.

@Adam *******

When was that please?

@Michael *******

I want to know how much time to allow before booking flights.

@Tod ********

Sorry. I misread it as saying insurance requirements are the same.

@Tod ********

Insurance is not required to extend an O visa.

Go for an O not an OA unless u only want in out in out for 2 years. Thats literally not metaphorically...555.

@Richard **********

You dont need it.

Emirates free inclusive insurance is still valid.