Removing paper conflicts after double-blind review process
Many, but not all, DBR conferences I am involved with do in fact remove blinding and conflicts at some point in the process, usually either shortly before or directly after final decisions have been made. The two downsides I see with this are as follows:


PC members get to see all review results, including the results of friends and students, a short time before they are sent to the authors. In practice this leads to the (small) advantage for well-connected authors that they know about the fate of their paper a few days ahead of others.
There may be cases where conflicts are declared not because two authors are friends or colleagues, but because of severe professional disagreements. In that case giving the conflicting PC member insight into the submitted paper, reviews, and review result at any point in time is a very large no-no.


At the end of the day, it is your decision as a chair how you want to implement DBR - there isn't a fixed set of rules that are given from a higher entity. However, please be transparent with your rules, optimally ahead of time. If you have not announced that conflicts would be lifted at some point in the process, I would personally avoid changing your mind mid-process.