Long layover at mumbai International Airport, need some help!

I have a 17 hrs layover at mumbai soon. My flight reaches at 11am and the next flight is at 5.30am on the next day. I am planning on going out of the airport, as this is my first time in mumbai. Right now my plan is to leave the airport around 2 pm, hit some food spots and come back to the airport by 9pm. My question is if they will allow me to come back into the airport at 9pm? ( A friend told me they may not allow to enter the airport that early since my flight is at 5.30am). I would really appreciate your help guys😌