--- a/testing/mozharness/configs/single_locale/try_android-api-15.py
+++ b/testing/mozharness/configs/single_locale/try_android-api-15.py
@@ -1,8 +1,10 @@
+import os
+
 BRANCH = "try"
 MOZILLA_DIR = BRANCH
 EN_US_BINARY_URL = "http://archive.mozilla.org/pub/" \
                    "mobile/nightly/latest-mozilla-central-android-api-15/en-US"
 
 config = {
     "branch": "try",
     "log_name": "single_locale",
@@ -20,16 +22,17 @@ config = {
     "tooltool_config": {
         "manifest": "mobile/android/config/tooltool-manifests/android/releng.manifest",
         "output_dir": "%(abs_work_dir)s/" + MOZILLA_DIR,
     },
     "exes": {
         'tooltool.py': '/builds/tooltool.py',
     },
     "update_gecko_source_to_enUS": False,
+    "nightly_build": True,
     "repos": [{
         "vcs": "hg",
         "repo": "https://hg.mozilla.org/build/tools",
         "branch": "default",
         "dest": "tools",
     }, {
         "vcs": "hg",
         "repo": "https://hg.mozilla.org/try",
@@ -43,17 +46,17 @@ config = {
     "hg_l10n_tag": "default",
     'vcs_share_base': "/builds/hg-shared",
 
     "l10n_dir": "l10n-central",
     "repack_env": {
         # so ugly, bug 951238
         "LD_LIBRARY_PATH": "/lib:/tools/gcc-4.7.2-0moz1/lib:/tools/gcc-4.7.2-0moz1/lib64",
         "MOZ_OBJDIR": "obj-firefox",
-        "EN_US_BINARY_URL": EN_US_BINARY_URL,
+        "EN_US_BINARY_URL": os.environ.get("EN_US_BINARY_URL", EN_US_BINARY_URL),
         "LOCALE_MERGEDIR": "%(abs_merge_dir)s/",
         "MOZ_UPDATE_CHANNEL": "try", # XXX Invalid
     },
     "upload_branch": "%s-android-api-15" % BRANCH,
     "ssh_key_dir": "~/.ssh",
     "merge_locales": True,
     "mozilla_dir": MOZILLA_DIR,
     "mozconfig": "%s/mobile/android/config/mozconfigs/android-api-15/l10n-nightly" % MOZILLA_DIR,