The RPRA have issued a directive regarding the number of birds permitted in a crate for transportation as per rule 127.

The total floor space in our crates is 949.63 sq inches

1 night in a crate all pigeons must have 44 square inches each

2 nights in a crate they must have 52 square inches each

more than 2 nights ie France 60 square inches each therefore inland no more than 21 birds per crate , on the channel 18 birds maximum per crate and France 14 birds these figures INCLUDE having your own crates during the YB season