--- a/lib/python/kickoff/__init__.py
+++ b/lib/python/kickoff/__init__.py
@@ -160,16 +160,29 @@ def get_l10n_config(index, product, bran
         if tc_task_indexes[platform]['ci_system'] == 'bb':
             mar_tools_url = "https://queue.taskcluster.net/v1/task/{taskid}/artifacts/public/build".format(
                 taskid=unsigned_task["taskId"]
             )
         else:
             mar_tools_url = "https://queue.taskcluster.net/v1/task/{taskid}/artifacts/public/build/host/bin".format(
                 taskid=unsigned_task["taskId"]
             )
+            if platform.startswith("mac"):
+                # FIXME: dirty dirty hack
+                if branch == "mozilla-beta":
+                    if product == "devedition":
+                        mar_tools_url = "https://archive.mozilla.org/pub/devedition/candidates/55.0b14-candidates/build1/mar-tools/macosx64/"
+                    elif product == "firefox":
+                        mar_tools_url = "https://archive.mozilla.org/pub/firefox/candidates/55.0b13-candidates/build1/mar-tools/macosx64/"
+                elif branch == "mozilla-release":
+                    # if we don't get releasetasks in-tree by the time 56 get
+                    # to release, we need to add here the last working release,
+                    # either that's 55.0 or 55.0.X mar/mbsdiff build on BB mac
+                    # native hardware - see bug 1388460 for more details
+                    pass
 
         # en-US binary lives all over the places!
         if platform.startswith("linux"):
             route = tc_task_indexes[platform]['signed'].format(rev=revision)
         elif platform.startswith("mac"):
             if tc_task_indexes[platform]['ci_system'] == 'bb':
                 route = tc_task_indexes[platform]['signed'].format(rev=revision)
             else: