@Raki *******

Just open the website and click on number 20, you see a list of numbers, who correspondent with the numbers above to see which long stay you can use.

Non Immigrant B or Extension of Stay based on working is one of them.

Problem solved

If you have the Extension of Stay based on being married with a Thai National you can not use that as basis for your mother to apply for the Non Immigrant O visa based on being a family member of an alien permitted a temo\porary stay in the kingdom.

You can read here: For your mother is it clause number 20 and yours is clause 18, which is not mentioned under possibilities if you open 20.

I guess you visited Immigration with lots of documents from your employer and got a new stamp with the text:

Extension of Stay is permitted up to xx/xx/xx (date)

You have to cancel this stay and your work permit, using the last day of employment with your current employer.

The new employer needs to meet the requirements to apply with you for a new Extension of Stay.

365 days and for the reason:

I'm over 50 years of age and willing to sit out the rest of my life in Thailand. OR short retirement

No, you fill in the amount of days corresponding with the application of Extension of Stay.

30 days if you like to extend a tourist visa or visa exempt

60 days if you apply to visit family

365 days if you want to work 1 more year

etc

I guess you have the big stamp from Immigration with in the secon line the text:

Extension of Stay permitted up to 4 May 2022.

This stay has to be cancelled by you using the last day of working, you may do this in advance to have time to leave the country or apply for a new Extension of Stay if you can meet the requirements.

The so called 90 days report is a report that you are 90 days inside Thailand. Counting the days inside Thailand only stops when you leave Thailand,

If you want to avoid 1 day at immigration for the 30 day extentsion, apply for the Single Entry Tourist Visa and get 60 days on entry. And in case of, possible to extend once with another 30 days.

You can apply during the last 30 days of your current admitted to stay period.

But be aware, rules are more strict so prepare a plan B.