Is it time to train ?

Ok, so our ybs have been doing really well, getting on for an hour and a half loft flying, but the last 2/3 days they seem to be lazy, they are on darkness and some of the earlier young are looking more like adults, and these look to be the ones that are holding the other later young birds back, so we are wondering if it's time to get them up the road and just loft fly the later bred ybs until they catch up with the first lot.

always a problem with early bred ybs as they start to take interest in eachother and have stopped ranging ....I would toss them no bother cant do any harm but stay away from Wednesdays and the weekend ,I have 2 sections for ybs different ages they wont mix until 2nd batch is training ...not that we have that many ybs only 28 but sometimes the older ones stop them ranging or at least that's what I have found