>However, on my last visit to immigration the officer was not happy as on the day when the deposit finishes the balance in my bank account is entered as 0 and then back up to 800,000 baht as I carry it forward for another year.
Who is withdrawing ht money and bringing it back up to the 800K THB? Is that you, or the bank?
1. On November 23rd, 2021, the poster entered Thailand on a 60 day single entry tourist visa. I knew they entered on a single entry tourist visa because the visa is stamped "TR". A single entry tourist is voided on entry. They could stay until January 21, 2022.
2. On December 6, 2021, the poster left Thailand.
3. On January 1, 2022, the poster returned to Thailand on a visa exempt. I know they entered on a visa exempt because of the ผ symbol next to the entry date. On a visa exempt, a person could stay for 29 days. They could stay until January 30, 2022.
You are on a 30 day visa exempt. You will need to get a 30 day extension of stay based on tourism. There is no advantage in waiting until the last day to get this extension of stay, because it is added on to your existing "admitted to" stamp.
2. >Thailand, which tourist visa will allow him to stay in Thailand the longest before extending?
I recommend a single entry tourist visa. This allows a person to stay for 60 days, extendable once for another 30 days.
>and then hopefully get him on the Thai Child Non-O Visa
Since you and him are not married, he will need to be granted parental rights by the Amphur office I believe. This is a simple process since you (the mother) are agreeing to it. It may take some time though, but I'm not sure. This can also be granted automatically if you and him are married.
Once he is granted parental rights, he can get an in-country Non-O visa based on raising a half-Thai child followed by a one year extension of stay based on raising half-Thai child. He can acquire a work permit on this extension of stay.