About a month ago we upgraded to Subversion 1.7. On Monday, we will be doing rolling upgrades of all of our Subversion repositories to the latest on disk format. There will be no overall interruption of service, although specific repositories will be unavailable while they are being upgraded.
This will give access to the latest Subversion features for all repositories.
We will be starting this process at 15:00 UTC and expect it to take around 10 hours to upgrade all repositories.
Note: If you attempt to access your repository while it is being upgraded, it will fail.