You may have to show PROOF of your DTV Visa to airline staff on check-in for your flight ✈️ to Thailand...even to the connecting airline staff. Or to the land border crossing entry Thai Immigration Officer.
Upon arrival into Thailand, show the DTV visa to the Thai Immigration Officer and look at the STAMP placed in your passport to be sure you are STAMPED in for 180 days.
DON'T LEAVE Thailand during the course of study. Thai Immigration Officers are cracking down on those who have a Thai language study Visa in their passport and leave Thailand during their course of study. That's a fact for Ed Visa holders... though uncharted waters for DTV Visa holders. BE CAREFUL
As it appears that you are Married to Thai, this is a great time to get the correct Thai Visa as Married to Thai. Then with a multiple entry permit you will never have to be concerned about your entry into Thailand.
Rest assured that this Post from TVA is the latest news on the real world happenings with the new rules. They deal with Thai Immigration visas and rules daily. AND I'm sure you MUST realize that whatever is published in Thai law is subject to its application among the 80+ Thai Immigration offices nationwide.