Towards end of 1944, Netaji Subhas Chandra Bose gave Dhillon the command of 4th Guerrilla Regiment also called the Nehru Brigade. His regiment distinguished itself in the battlefield. The Nehru Brigade was to hold the Irrawaddy River from Nyaungu in north to Pangan in south, both towns inclusive, and to hold the enemy crossing the Irrawaddy at those places.
Dhillon formed an advance party from 9th Battalion and left for Pagan on December 29, 1944. Dhillon ordered the move of battalions to leave Myingyan by February 4, 1945 so as to be in their respective positions by February 8, 1945. Dhillon ensured all the arrangements. The Nehru Brigade held the Irrawaddy as planned. Dhillon kept his Headquarters at Tetthe during this operation. On February 12, 1945 the enemy planes carried out saturation bombing on INA defences. On 13/14 February night enemy launched an assault in front of the 8th battalion deployed at Pagon. These assaults were failed and the enemy had to withdraw. The Nehru Brigade kept on holding the Irrawaddy and this was the first victory of INA. After the failure at Pagan the enemy tried another assault crossing opposite Nyaungu by using outboard motors and rubber boats. This assault was also failed and hundreds of enemies were killed or drowned. Having failed the enemy had no other choice but to retreat. This was another victory of INA. This could not sustain and INA had to withdraw and Dhillon had to proceed to Pagan.
Dhillon reached Pagan on February 17, 1945. On February 23, 1945, General Shah Nawaz visited the Commander of Khanjo Butai and discussed co-ordination of Indo-Japanese operations in the Popa and Kyauk Padaung area. Col. Sahgal was given the task to prepare Popa as a strong base with the view to take up an offensive role. Dhillon's Regiment, the 4th Guerrilla, was assigned the duty to check the enemy advance on to Kyauk Padaung from the west, where the British had established a strong bridgehead at Nyaungu. This was to be achieved by carrying out an extensive and persistent guerrilla warfare in the area between Popa, Kyauk Padaung line in the east and as far forward towards the Irrawaddy as possible as to deny the enemy the use of Nyaungu-Kyauk-Padaullg-Meiktila metalled road for supplying reinforcements and supplies to his forces fighting in the battle of Meiktila. Shah Nawaz arrived Popa on 12 March 1945 and relieved Dhillon forthwith to join his regiment.
On April 4, 1945 his Division Commander, Colonel Shah Nawaz Khan, ordered Dhillon to return from Khabok to Popa. By then 4th Guerrilla regiment had been in that area waging guerrilla warfare for over five weeks. Mount Popa and Kyaukpadaung was one pocket of resistance, which had so far defied all British attacks. Under constant raids by INA the British forces were forced to use longer routes that caused the British loss of time, greater consumption of petroleum products and frequent breakdowns of vehicles.
From the beginning of April 1945 the strategic situation began to change rapidly. The enemy launched a three-pronged attack on Mount Popa and Kyaukpadaung area. On 5 April 1945 Dhillon was allotted the defence of Kyaukpadaung, south of Popa. In the second week of April there was daily bombing from air. Under the cover of this barrage the British forces advanced in their heavy tanks and armoured vehicles. There were very heavy casualties. The INA could not organize any defence. 2nd Division of the INA was to withdraw to Magwe, 100 miles (160 km) south on Irrawaddy. After completing the task of withdrawing from Magwe, they came to a village called Kanni.
In the meantime, the Burmese army has declared war against Japan, and as such, the villagers did not co-operate with INA. Their retreat was fully under the control of General Aung San's Army under the new name of People's National Army, after having established a parallel government extending their hold over about 50 villages. They crossed Irrawaddy at Kama to reach Prome on May 1, 1945. Most of INA officers and men could not cross the river and they were stranded on the east bank of Irrawaddy. It was apparent by then, that they had lost the war. Rangoon had already been vacated. From Prome they took southeasterly direction to retreat through the jungles of the Pegu Yomas. Eleven days after leaving Prome, they reached at village called Wata about 20 miles (32 km) west of Pegu. There they learnt that Germany had surrendered. Japan was being heavily bombed daily. The British forces had occupied Pegu. Rangoon fell during the last week of April. Herein they decided that the surviving forces of INA should surrender to the British.