Rebalance progress bar needs to be clearer when moving multiple buckets

The current implementation shows the rebalance bar from 0-100% for the entire rebalance, yet it does one bucket at a time and the percentage values are for each bucket moving within the whole process.

i.e., with 3 buckets, the rebalance bar goes from 0-33% for the first bucket, 34-66 for the 2nd and 67-100 for the third, but there's no indication of this to the user.