The operation to relieve Tobruk gradually progressed from 18 November 1941

We learn that the Eighth Army movement forward built confidence in the men that their force was strong and could beat the enemy. The men were isolated and without information about the attack progress. All they would hear were rumors. They would occasionally be in a fight with the enemy, but they lacked knowledge about the larger picture.
The men in Tobruk were especially isolated. Their impression was that the operation was behind schedule and that there was a great deal of confusion. All the men knew was their own situation, without knowing anything about what the grand design included. They thought that they knew about a proposed connection with the relief force at Ed Duda. That seemed like a main objective, so that when they received news about developments, they had trouble making sense of what they heard or read.
Tobruk got the "Tug" code word on both 18 and 19 November. "Tug" meant that they were not to attack. The 2/13th Battalion only received some news about the battle late on 19 November. The information that they did receive was old, since the date was from 10:45am on 18 November. The information was useless, because the location of British tanks was wrong. There were still no British tanks anywhere near Ed Duda, at least not within 30 miles.
Early on 20 November, they received a message about British tank locations early on 19 November. The 7th Armoured Brigade was moving to Sidi Rezegh. The 22nd Armoured Brigade was moving towards Bir el Gubi. The 4th Armoured Brigade, equipped with Stuart tanks, fought a battle with sixty enemy tanks and had driven then to the north. The men in Tobruk had expected that the South Africans would take Sidi Rezegh, but they were reported to be at Ed Gubi, very far to the south. The men in Tobruk saw forty British fighters fly over. The diarist from the 104th RHA wrote that he had not seen anything like it before. Somewhat later, the men in Tobruk could see the flashes of guns firing and tracers into the sky from near Sidi Rezegh. They men also heard about a large tank battle the previous day where the British had knocked out 27 enemy tanks for the loss of 20 of their own. The men knew that there were units from the frontier close to the Tobruk perimeter. The attackers seemed to be achieving what was desired.
The next thing that the men in Tobruk learned was that the "Pop" code word was finally issued by XXXth Corps. They would sortie from Tobruk the next morning. More detailed instructions were issued by telephone from the Tobruk phone network. This is based on the account in Vol.III of the Australian Official History.