--- a/testing/taskcluster/mach_commands.py
+++ b/testing/taskcluster/mach_commands.py
@@ -25,17 +25,17 @@ from mach.decorators import (
 ROOT = os.path.dirname(os.path.realpath(__file__))
 GECKO = os.path.realpath(os.path.join(ROOT, '..', '..'))
 
 # XXX: If/when we have the taskcluster queue use construct url instead
 ARTIFACT_URL = 'https://queue.taskcluster.net/v1/task/{}/artifacts/{}'
 
 DEFINE_TASK = 'queue:define-task:aws-provisioner-v1/{}'
 
-DEFAULT_TRY = 'try: -b do -p all -u all'
+DEFAULT_TRY = 'try: -b do -p emulator-jb,emulator-kk,emulator,emulator-ics -u none'
 DEFAULT_JOB_PATH = os.path.join(
     ROOT, 'tasks', 'branches', 'base_jobs.yml'
 )
 
 def merge_dicts(*dicts):
     merged_dict = {}
     for dictionary in dicts:
         merged_dict.update(dictionary)

--- a/testing/taskcluster/tasks/builds/b2g_emulator_jb_debug.yml
+++ b/testing/taskcluster/tasks/builds/b2g_emulator_jb_debug.yml
@@ -28,9 +28,9 @@ task:
       level-{{level}}-{{project}}-emulator-jb-debug: /home/worker/workspace
       level-{{level}}-{{project}}-emulator-jb-debug-objdir-gecko: /home/worker/objdir-gecko
     env:
       TARGET: 'emulator-jb'
       B2G_DEBUG: 1
       TOOLTOOL_MANIFEST: 'b2g/config/emulator-jb/releng-emulator-jb.tt'
       # This setting is to offset the number of arugments passsed into docker run
       # for https://github.com/docker/docker/issues/14203
-      DOCKER_OVERRIDE: 1
+      DOCKER_OVERRIDE: '{{project}}'

--- a/testing/taskcluster/tasks/builds/b2g_emulator_kk_debug.yml
+++ b/testing/taskcluster/tasks/builds/b2g_emulator_kk_debug.yml
@@ -28,9 +28,9 @@ task:
       level-{{level}}-{{project}}-emulator-kk-debug: /home/worker/workspace
       level-{{level}}-{{project}}-emulator-kk-debug-objdir-gecko: /home/worker/objdir-gecko
     env:
       TARGET: 'emulator-kk'
       TOOLTOOL_MANIFEST: 'b2g/config/emulator-kk/releng-emulator-kk.tt'
       B2G_DEBUG: 1
       # This setting is to offset the number of arugments passsed into docker run
       # for https://github.com/docker/docker/issues/14203
-      DOCKER_OVERRIDE: 1
+      DOCKER_OVERRIDE: '{{project}}'