Reddy had challenged the state government decision about not extending his services in the wake of a CBI inquiry pending against him for allegedly amassing disproportionate assets.
Reddy is to be superannuated on September 30.
The state government had yesterday rejected his representation in the case, following which Reddy immediately filed an application seeking interim relief for him to continue for another year.
However, the CAT bench, too, rejected his interim plea today.
He said Supreme Court's directions are specific about the appointee to the post of DGP being in office for a minimum period of two years from the date of his appointment, irrespective of the date of superannuation.
Based on a complaint filed by senior IPS Officer Umesh Kumar, the apex court on September 6 ordered a CBI probe against Reddy for allegedly amassing disproportionate assets along with his wife.
It also slammed the state government for not conducting any probe against Reddy when a copy of a complaint against him was forwarded by the Centre.
A bench of justices BS Chauhan and SA Bobde directed CBI to conduct the probe and file a status report within four weeks.
