@Andy *******
there is no 6 month visa of any kind. There are 60 day, 90 day, and 1 year visas, and extensions, but there are no 6 month visas. There is a multi-entry tourist visa that is valid for 6 months from the time it was issued, but then when you enter Thailand you get a 60 day entry stamp that you can extend for another 30 days once before you have to leave Thailand. Being that your multi-entry visa still has time left in the 6 months from the time it was issued, you can cross the border, and come right back to get another 60 day entry stamp, and can do another 30 day extension. You can enter and leave Thailand as many times as you want in that six months, but there is no 6 month visa entry stamp. The only way someone would get stamped in for only 6 months is if their passport expires in 6 months when applying for the one year extension under a different visa extension type, or with a long term visa requiring health insurance, but the insurance policy is only for 6 months. Those are the only situations where someone would be stamped in for 6 months. You are way off in your supposed details.