NSUT Civil allotted, paid 95k. Should I go for cancellation or wait for upgradation/spot round?

Hi guys,
I have been allotted NSUT Jaffarpur - Civil branch and I’ve already paid the 95k seat acceptance fee. But I don’t want to pursue Civil.

I have 2 doubts:

1. Should I go to NSUT tomorrow for admission cancellation, or is there still a chance for upgradation to DTU CSE in upcoming rounds?
2. If I want to participate in spot rounds, do I need to pay the college fees first?

Also, if I don’t go for cancellation tomorrow, will my admission get automatically cancelled?

Any seniors who went through this please help. Thanks!