This also works from Miami (I'm sure) and Canadian eastern cities (I think); round trips from all cities are good until either June 6 or June 13. Carry-ons allowed, but yes no checked bags. Given summer fares to Europe from $270 - $450 r/t I agree that this is an outstanding deal.
Also: base fares are as low as $12, with YQ making up the rest. So if you are good at losing fuel charges somehow...