@Brian ******
ah OK, a standard 30 day extension to a tourist or excempt stamp is possible now, but if your planned stay is over 60 days, then you need to bounce out/in to get a new visa beyond the 60 days stay, but you can then utilise the unused 60 day tourist visa. It's 'potluck' whether a local immigration office will amend that 30 day exempt stamp to a 60 day tourist stamp, but the majority of cases have had to return to point of entry to get that amended, which is a ball ache if you're swinging in a hammock on koh Lipe, having arrived in Bangkok. 'All depends on the immigration officer on the day'.