May 1st has nothing to do with visas. May 1st is when the digital arrival card starts. It's just replacing the paper form they used to hand out on the plane.
If you're from a visa exempt country, you can get a 60 day entry stamp before May and after May.
You need to contact your airline. They are the only ones who can tell you if they will let you fly or not.
Thailand does not have a rule about requiring 6 months visa validity to enter. The rule for Thailand is that you must have enough time on your passport to account for the stamp you would receive. If that's a visa exempt entry, then your passport only needs to have 60 days validity at the time you enter, and they will allow it.
BUT most airlines will not let anyone fly if their passport is valid for less than 6 months. So regardless of Thailand's rules, there's a high likelihood that your airline won't take you to Thailand.
(The only 6 month rule Thailand has it that you must have 6 months left on your passport in order to apply for a visa through an embassy)