as soon as it rains i put my yb,s out .as the yb,s will fly the rain does not stop them. just know i have old birds out when the old birds land i let about half the ybs out so old birds are back up in the sky when then birds land again the rest of the yb,s go out back up in the sky . i do not flag birds up as on race day birds are sure to be trap shy. it works for me.plus yb,s bomb about so old birds have to pick up the pace to keep up with them . an easy hour plus flying not glideing about.