that isn't Koh Samui? We've booked flights to Bangkok (avios) with the intention of getting internal flights to a beach destination. All my research says the Koh Samui area is best in July but there seems to be a monopoly on the route now and the short hop is coming in nearly 1k.
I'm looking into it now and thinking about alternatives. Koh Samet has come up but wondering if this will be too small. Teen Dds want to snorkel. We have two weeks and may add in Chiang Mai ( return flights from BK are cheap). First time I've been to Thailand though DH been to Bangkok and travels a lot in Asia for work.