dear aspirant,

You can participate in CSAB even after you get seat allotted in JOSAA.CSAB(Central Seat Allocation Board) counselling is conducted separately .It is different from JOSAA.

The CSAB 2019 process will start after the JoSAA 2019 ends. A separate notification will be issued for CSAB 2019 registration. Candidates will be required to register in online mode for participating in CSAB 2019. It is important that candidates first check the complete eligibility criteria of all the channels and then only proceed to fill the application form of CSAB 2019 through the respective channel. Those candidates who will register for CSAB will have to fill their choice of colleges and courses in the order of their preference. The seat allotment of CSAB 2019 will be done on candidates’ JEE Main merit, choice filling and seat availability.

best of luck