archers wouldn't do the because unlike a gun you cannot hold it loaded for long. So your order would be draw and fire. You can of course hold abow drawn for maybe a minute - but why do that when you can fire 6 arrows in that time which might hit.
If the enemy is out of range you might wait with an arrow knocked but not drawn - but if that is what they were doing the order would be to draw. there is no real point of such an order though - archers are themselves smart enough to estimate their own range (which as the other response pointed out was not the same for every archer), and thus make their own decisions. The only reason to hold fire until everyone was ready was if the combine fire was devistating enough - but there is every reason to think combined fire wouldn't be devistating.
If the enemy is out of range you might wait with an arrow knocked but not drawn - but if that is what they were doing the order would be to draw. there is no real point of such an order though - archers are themselves smart enough to estimate their own range (which as the other response pointed out was not the same for every archer), and thus make their own decisions. The only reason to hold fire until everyone was ready was if the combine fire was devistating enough - but there is every reason to think combined fire wouldn't be devistating.