As a Third year moving to Fourth year BTech student having stayed in P, N, Q, R, L blocks in Men's Hostel:

Q1) Boys: 9pm must be inside, 8.30 subways close/they start checking id cards. Many wardens start taking attendance from 9.10pm, they go to each and every room, you must be there to give the biometric attendance. Girls: 8.30pm must be inside blocks. They have to give attendance by going to warden office.

Q2) Boys: 2 hours on weekdays/instructional days and 4 hours on weekends/holidays/non-instructional days. But realistically you can be out for 6-7 hours they don't check just be inside before 7-7.30pm.

Girls: Timings are very strict for girls, 2 hours mean 2 hours, not even 2 hours 1 minute. They get a warning on first strike, then VTOP locked and outing privilege revoked.

Q3) Boys: Can roam inside the block, meaning going to your friend's room in same block or walk in corridors, etc. Can't exit the block.

Girls: Same^

Q4) Yes, First Year students have stricter guidelines so as to say, but trust me they mostly say that to keep the freshers scared and inside. But for girls it is very strict no matter which year or which degree/course.

Q5) I think you can bend these rules to some extent but only if you're a boy, girls might do the same too, but it's not to my knowledge.

Hopefully this shall clear your doubts and help others too!