In 1945-46 the situation was very unstable in India, with the
Indian National Army trials, general elections, rioting, strikes, and mutinies, culminating in the Bombay mutiny of February 1946. The INC was also planning a nationwide strike at the time. In March 1946 the Attlee government sent the Cabinet Mission to discuss the transfer of power to Indian leadership.
Without this concession, the INC would have called the strike and ground the country to a halt. The British can't govern without the co-operation of Indian elites, official, and soldiers and would very quickly be forced to set a deadline for withdrawal and negotiation, or a very sudden and messy exit. The British could not control communal violence in 1945-47 OTL and this would be much much worse.
After the failure of the Simla Conference in 1945, Wavell, Churchill's Viceroy was planning for this eventuality whereby the British would transfer power to the INC and evacuate to the Punjab. It would not really be a 'war of independence' in any sense, more a humiliating and rapid exit.
An interesting consequence of more confrontation with the British government in this period could be a much more unified nationalist movement and less communalism than in OTL, possibly even an united India as a looser federation with the Muslim majority provinces.