If one resigns with some months remaining on a work visa, can one stay without problems (and assuming the work permit is cancelled by the employer) ?
TLDR : Answer Summary
When resigning from a job and holding a work visa, your ability to remain in Thailand depends on whether your visa is an entry visa or an extension based on your work. If it's an extension linked to your employment, you must leave the country upon resigning as you cannot stay after canceling your work permit. However, if you hold a visa that allows entry, you can stay until the end date of your current permitted stay, as long as you are within the first 90 days after entering Thailand.