Estimate: 30 minutes
The data to calculate the ETA (average speed, how many bytes are left) is already available in the sync progress report, so most of the work would just be formatting the ETA for human readability. No server side changes necessary at all.
Mike, this is a command-line client feature request that does not affect Katello. I don't think it should block sat6.
Agreed, we can already show iso progress with what we have.
Moved to https://pulp.plan.io/issues/187