Hello Shiva, Exam date and Time always remain fixed until and unless there is a leak of paper. It can't be changed as it is allotted by official authority. So, under such circumstances (same time and date) you have to skip one. All you can do is apply for the one exam again... All the best

Hello Shiva, TS PGECET 2018 is from May 28 to 31, 2018 (online mode). TS PGECET 2018 Test Schedule mentioned in below link, kindly go through it to clear you doubt: 

https://engineering.careers360.com/articles/ts-pgecet

All the best