During the battle officers whose business does not require them to visit the General Staff Office will make all inquiries at this office for information as to the progress of the operations.
Battle Instructions No. 20
CAVALRY
1. The First Cavalry Brigade, plus one company of Whippet Tanks attached, comes under the command of the Australian Corps Commander at 9 p.m. on Y/Z night.
2. Its function is to assist in carrying out the main Cavalry rôle by seizing any opportunity which may occur to push through this Corps front.
3. The First Cavalry Brigade will operate north of the Amiens—Chaulnes railway in conjunction with 5th Australian Division. It will move from its assembly position in Square n.32 under orders of G.O.C., 1st Cavalry Division, via the southern side of Bois de l'Abbé.
It will cross to the north side of the railway east of Villers-Bretonneux.
It will push forward patrols to keep in touch with 8th and 15th Australian Brigades.
After crossing the railway the main body of 1st Cavalry Brigade will march roughly parallel to it, keeping close touch with the remainder of 1st Cavalry Division to the south.
4. If a break in enemy's resistance occurs, the remainder of the 1st Cavalry Division may be employed in support of 1st Cavalry Brigade.
5. Command of 1st Cavalry Brigade will pass from Australian Corps to the 1st Cavalry Division when the Infantry reaches the red line unless the brigade is required in the area south of the Australian Corps to exploit success gained before that hour. This will be determined by G.O.C., 1st Cavalry Division, who will inform Australian Corps and 5th Australian Division, and issue orders direct to 1st Cavalry Brigade.