Do I need to cancel my Education visa in Thailand before applying for a DTV after my extension expires?

The individual is currently on an education visa in Thailand and is planning to leave for Lao on the expiration date of the second extension. They are uncertain whether they need to cancel the education visa or if they can simply leave the country once the extension expires. The responses indicate that it is necessary to cancel the education extension at immigration, which involves obtaining a letter from the school confirming the end of studies. However, if the user does not intend to continue with the education visa upon return, they may leave before the last stamped date and the visa would automatically cancel.