The 22nd Guards Brigade, a familiar unit to those who have long studied the North African Campaign, was holding Halfaya pass. Gott's Support Group was operating in the area between Halfaya and Sidi Barrani. In the Support Group, you had units such as the 11th Hussars, the 7th Armoured Division reconnaissance unit. Colonel Herff was in command of the German units near Halfaya and the Egyptian border. The Support Group raided German transport near Fort Capuzzo and Sidi Aziz. This was a minor British operation, but the way Colonel Herff reported it to Rommel made it sound bigger than it was. Rommel was getting very anxious about the situation near Bardia and Salum. If they were lost, it would endanger the effort to attack Tobruk. At this point, Rommel was saying that their loss would cause the siege of Tobruk to be removed. The suggested solution was to use aircraft to carry reinforcements and supplies to Tobruk. They would need to use submarines near the coast between Tobruk and Salum.
General Halder decided to send General von Paulus to North Africa to talk to Rommel and to get a sense of the true situation. The staff did not trust Rommel and was at the point of losing confidence in him. This might seem strange, given Rommel's success, but you have to remember that this was in the lead up to the attack on Russia on 22 June 1941, and that knowledge was having an impact at the German Army Command. The problem was that the Germans did not know the true situation of the British and Australians, and thought that they were in a better position than they actually were.
There was concern in Tobruk about the defenses against air attack, because heavy losses had been taken on 21 April 1941 due to an attack by 24 German bombers with 21 fighters. The quay was damaged and two ships were sunk. Two more were disabled. British Hurricane fighters were able to shoot down four German aircraft. In response to the attack, the British anti-aircraft gun commander, Brigadier Slater, proposed to start using a barrage pattern of fire, rather than shooting at individual aircraft. On April 23, the barrage defense showed its effectiveness. This is base on the account in Vol.III of the Australian Official History.