Bullshit different heights possibly when flying in different directions at different times. North versus south and all good libs. What happens when a north road convoy has been turned and they fly by lib site of a south road convoy at time of release ...no height restrictions there clashing does take place ....its harder for young birds to navigate and when they fly that far in the wrong direction ..what feed where they given?...enough fuel to get back from a 100 mile race which has just turned into a 2/300 mile race?? Rosscarberry a few years back, 250 to me heading north, i got 2 cork pigeons in that where released in Malin Head 300 mile to cork south, one of mine was reported in Youghal 30 miles east of cork...where was the height ratio/ to wind there, or was it just coincidence? fact from me