Hi Mo, the bright green ones are fresher but I don't know how new. I'd say weeks or months rather than days - just a wild guess.
I think I've read that the clumping occurs as they pass through the intestines not when they're in the GB/Liver as supposedly they couldn't get through the bile ducts. But it's a big mystery as doctors tell us the bile ducts are small and yet some of us are getting big stones out AND THEY ARE DEFINITELY NOT OLIVE OIL LUMPS. So far I think Blueduck is the champion but I don't know if hers was really a clump or one big stone.