rebate for individual

For which Assessment Year...?

A.Y. 17-18 Rebate of 5000 ( if Total Income does not exceed Rs. 5,00,000).
A.Y. 18-19 Rebate of Rs. 2,500 ( If Total Income does not exceed Rs. 3,50,000)

Advise:
It should also be noted that in order to curb fake investments/loan , AO may apply section 68. So assessee should have a source of income to prove the income.