hi,

see you did not mention which pgcet exams you are asking about, there is AP PGECET, TS PGECET.

for appgecet  counselling process , There is a separate provision of registration for GATE and GPAT qualified candidates.

for tspgecet gate qualified students will be given preferences, also they are exempted to appear in tspgecet exams, you need to apply separately for registration.

so since you have valid gate score you may apply for counselling of appgecet and tspgecet both.