Perforce users who switched to Review Board 1.5.2 and RBTools 0.3.1 this week hit an unfortunate problem updating review requests with change numbers. It turns out there's a validation error in our new API involving change numbers, which we'll be getting to soon.
For now, RBTools 0.3.2 is out the door, and works around this breakage by falling back to the old API. If you're on Perforce, you'll want to upgrade and make sure things are back to normal. Sorry about that!
There's also a fix for parsing CVSROOTs that don't have a username in the path, and choosing Mercurial over Perforce in a Perforce repository when there's an existing Mercurial user configuration.
As always, release notes are available.