Relief u/s 89/1

No need.

Only file ITR for AY 2019-20 with arrears claim of earlier year/s.

Last years ITR is not required to be filed, You have to file ITR of fy 2018-19 and form 10E to claim relief under section 89. 

Thanks, highly obliged.

Hafiz

Thanks. Highly obliged

Hafiz

Not required 

Form 10E has to be filed online first before you e-file the returns