budget 2019

When any budget comes, it becomes effective from 01/04/20** of the same year.
for example for the budget 2019 previous year will be 01/04/2019 - 31/03/2020.
And AY will be 2020-21, So ITR of AY 2020-21 will prepared on basis of budget of 2019.
And TDS rate will applicable from 01/04/2019 onwards.
Generally the budget comes on 1st of February of each year but in case of change in government the budget announced again by the new government.