The validity period for the Visa as mentioned is 6 months from date of issue. However, your permission to stay in Thailand be 60 days from the date of entry which can be extended for another 30 days at Thai Immigration. If you depart and return to Thailand prior to the expiration date of the "Visa", you again receive 60 days which can again be extended.
For example, if your METV "Visa" expires on October 15, 2022 and you enter Thailand on October 14, 2022, your permission to stay stamp will be until October 12, 2022 and extended for an additional 30 days until January 12, 2023.