The calendar comes about through dividing the solar year into equal parts based on the equinoxes and solstices. Lammas is halfway between the Summer Solstice and the Autumn Equinox. This year that's on August 7th. That's the date of Lammas. If you want to tell me that New Year's Day, next year, is on January 15th, please go ahead, but the rest of us will watch the fireworks a little more than a fortnight previously. It's the same with the neo-drewids. It's like asking me to respect the lass that lives near me and touches and whispers to every lampost she passes.
I'm very wary of setting cross quarter days into hard and fast dates, simply because they are actually a modern interpretation of the original, which in all likely hood wouldn't have been held to any set date but a period of time, or an occasion/event. Today's 'set' dates are more for convenience than anything else.
But if you want August 7th.... you go ahead...lol, I'll stick with the 1st, although unless we get some serious sun between now and the first, I might be struggling to find a sheaf of corn that's ripe :) - anyone got some yellow spray paint? that might be a good plan B.
BB
Sian