Songkran starts on 13th this year so I'd get onto it straight away. You normally need a resident certificate and im not sure how long that takes in HuaHin
We are all talking about the 6 month METV. (Which is a Visa by the way). Yes, you only get stamped in for 60 days at a time and can extend it by 30 days at immigration within Thailand. It is not valid for 6 months from the date it is issued it is valid for 6 months from the date it was first used. Why would they have 2 dates on it .....!!
I think the terminology is confusing people. When the Visa is issued you have to use it withing a certain period which will be stamped on the Visa ( in the diagram Brandon provided this is section 4). You can start to use the visa at any point from when you recieved it to the use by date. The first day you actually use ot is when the duration starts so for a 6 month visa if you get it issued on Jan 1st and use it to enter Thailand on Jan 2nd it lasts 6 months from Jan 2nd. If you get it issued on Jan 1st but dont use it until Feb 1st it will last 6 months from Feb 1st and not 6 months from Jan 1st.
Everything i said your photo confirms. You get issued the visa by the Thai Government and have to use it within a certain time. If its a 6 month visa the clock starts ticking the day you first enter Thailand and not the date it was issued. The date you must enter Thailand is within a certain time from when it was issued.
I've just reread and see he doesn't want to use the METV for his initial trip. I think he can even just artive without a visa and get stamped in for 45 days and extend that for a further 30 days. He then needs to do a border bounce and can come back in again without a visa for another 45 days plus get another 30 days extention. Suggest to put your mind at ease you ask this question on the group Thai Visa Advice as the moderators are very clued up.