Scheduled builds and builds running on remote agents don't seem to switch to a new source root in the build directory

There's a couple of builds on JBAC2 (some of the branch builds), where we switched from the 3.12 branch of the JIRA source to the 3.13 branch. The builds configuration reports the source path correctly as 3.13. However when you look in the actual build directory on the server, 'svn info' shows that the build is still building the 3.12 branch.

This seems to be true for scheduled builds (such as https://jira2.bamboo.atlassian.com/browse/JIRAFUNCBRA-JDK14) and builds that have run on remote agents (the source on the remote agent's box is still from the old branch). Since we'll end up testing the wrong source without knowing this is pretty bad!