diff --git a/scripts/build-unit-test-docker b/scripts/build-unit-test-docker
index a1e0312..db248fe 100755
--- a/scripts/build-unit-test-docker
+++ b/scripts/build-unit-test-docker
@@ -471,10 +471,13 @@
         if gerrit_project == self.package and gerrit_rev:
             return False
 
+        # URL escape any spaces.  Gerrit uses pluses.
+        gerrit_topic_escape = urllib.parse.quote_plus(gerrit_topic)
+
         try:
             commits = json.loads(
                 urllib.request.urlopen(
-                    f"https://gerrit.openbmc.org/changes/?q=status:open+project:{self.package}+topic:{gerrit_topic}"
+                    f'https://gerrit.openbmc.org/changes/?q=status:open+project:{self.package}+topic:"{gerrit_topic_escape}"'
                 )
                 .read()
                 .splitlines()[-1]