UDD still breaking with tip of lp:bzr-builddeb

I'm getting the following traceback running tip of lp:udd and lp:bzr-builddeb locally:

Traceback (most recent call last):pply phase 2/3
  File "/srv/package-import.canonical.com/new/scripts/import_package.py", line 1155, in <module>
    only_before=options.only_before))
  File "/srv/package-import.canonical.com/new/scripts/import_package.py", line 1064, in main
    possible_transports=possible_transports)
  File "/srv/package-import.canonical.com/new/scripts/import_package.py", line 946, in handle_collisions
    if clean_collision(importp, suite, db, temp_dir, download_dir, name, updates_branch):
  File "/srv/package-import.canonical.com/new/scripts/import_package.py", line 880, in clean_collision
    return check_same(importp, db, revid, name, updates_branch, temp_dir, download_dir)
  File "/srv/package-import.canonical.com/new/scripts/import_package.py", line 846, in check_same
    importp, db, revid, name, updates_branch, temp_dir, download_dir)
  File "/usr/lib/python2.7/dist-packages/bzrlib/cleanup.py", line 131, in run
    self.cleanups, self.func, self, *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/cleanup.py", line 165, in _do_with_cleanups
    result = func(*args, **kwargs)
  File "/srv/package-import.canonical.com/new/scripts/import_package.py", line 867, in _check_same
    pull_debian=False)
  File "/srv/package-import.canonical.com/new/bzrplugins/builddeb/import_dsc.py", line 1267, in import_package
    pull_debian=pull_debian)
  File "/srv/package-import.canonical.com/new/bzrplugins/builddeb/import_dsc.py", line 1140, in _import_normal_package
    package, version.upstream_version)
  File "/srv/package-import.canonical.com/new/bzrplugins/builddeb/import_dsc.py", line 715, in pull_upstream_from_branch
    "Can't pull upstream with no tree"
AssertionError: Can't pull upstream with no tree

The particular import being tried is ./import_package.py --local-branches python-configglue, after swapping out the upstream-0.9 tags for upstream-0.9pre1 tags.