If you have chosen float then in up-coming (next) round, 2 things can happen

1. You can get a seat having a higher preference than your current allotted seat.

In that scenario you will lose your current allotted seat.

2. No upgradation. 

Hello aspirant,

In-case you have chosen float option, then you will be able to participate in next round of counseling.

This will enable you to upgrade your choice if seats are vacant in upper choices. So it is a good chance to increase chances of admission of your choice.

However, if you don't get any seat in upper choices and your current option gets filled, then you will lose your current seat.

So I will advise you to take decision carefully.

Hope this helps