In Bamidbar 1:14, when listing the heads of the tribes, Gad comes between Asher and Naftali and is in the 11th position.
However, when citing the tribal census, Gad appears after Shim'on and is in the 3rd position. (See verse 24.) The rest of the tribes' censi (is that the plural of "census"?) appear in the same order as the tribal leaders' listings.
Why is only Gad moved?