Interim Relief vs HRA Exemption in Income Tax Calculation

salary components are Band Pay, grade Pay,DA, HRA,MA & Interim Relief (from 01-07-2017)
HRA exemption from Income
= least of A,B & C below
A = HRA received with Salary
B= 40%/50% of band pay+Grade Pay+DA
C=House Rent paid to owner of the House – 10% of band pay+Grade Pay+DA

X
is Interim Relief (from 01-07-2017) be included to “C” and it to be taken as
C=House Rent paid to owner of the House – 10% of band pay+Grade Pay+DA+Interim Relief

Y
which is correct “X” or “Y” .
Pl. confirm.