--- a/taskcluster/ci/build/windows.yml
+++ b/taskcluster/ci/build/windows.yml
@@ -800,17 +800,17 @@ win32-mingw32/opt:
 win32-msvc/debug:
     description: "Win32 MSVC Debug"
     index:
         product: firefox
         job-name: win32-msvc-debug
     treeherder:
         platform: windows2012-32/debug
         symbol: Bmsvc
-        tier: 2
+        tier: 1
     worker-type: aws-provisioner-v1/gecko-{level}-b-win2012
     worker:
         max-run-time: 7200
         env:
             TOOLTOOL_MANIFEST: "browser/config/tooltool-manifests/win32/releng.manifest"
             PERFHERDER_EXTRA_OPTIONS: msvc
     run:
         using: mozharness
@@ -833,17 +833,17 @@ win32-msvc/debug:
 win32-msvc/opt:
     description: "Win32 MSVC Opt"
     index:
         product: firefox
         job-name: win32-msvc-opt
     treeherder:
         platform: windows2012-32/opt
         symbol: Bmsvc
-        tier: 2
+        tier: 1
     stub-installer:
         # Beta and release use a stub-requiring update channel
         by-project:
             default: false
             mozilla-beta: true
             mozilla-release: true
     worker-type: aws-provisioner-v1/gecko-{level}-b-win2012
     worker:
@@ -872,17 +872,17 @@ win32-msvc/opt:
 win64-msvc/debug:
     description: "Win64 MSVC Debug"
     index:
         product: firefox
         job-name: win64-msvc-debug
     treeherder:
         platform: windows2012-64/debug
         symbol: Bmsvc
-        tier: 2
+        tier: 1
     worker-type: aws-provisioner-v1/gecko-{level}-b-win2012
     worker:
         max-run-time: 7200
         env:
             TOOLTOOL_MANIFEST: "browser/config/tooltool-manifests/win64/releng.manifest"
             PERFHERDER_EXTRA_OPTIONS: msvc
     run:
         using: mozharness
@@ -905,17 +905,17 @@ win64-msvc/debug:
 win64-msvc/opt:
     description: "Win64 MSVC Opt"
     index:
         product: firefox
         job-name: win64-msvc-opt
     treeherder:
         platform: windows2012-64/opt
         symbol: Bmsvc
-        tier: 2
+        tier: 1
     worker-type: aws-provisioner-v1/gecko-{level}-b-win2012
     worker:
         max-run-time: 7200
         env:
             TOOLTOOL_MANIFEST: "browser/config/tooltool-manifests/win64/releng.manifest"
             PERFHERDER_EXTRA_OPTIONS: msvc
     run:
         using: mozharness

--- a/taskcluster/taskgraph/transforms/signing.py
+++ b/taskcluster/taskgraph/transforms/signing.py
@@ -117,17 +117,17 @@ def make_task_description(config, jobs):
             build_platform = dep_job.attributes.get('build_platform')
             treeherder.setdefault('platform', _generate_treeherder_platform(
                 dep_th_platform, build_platform, build_type
             ))
             treeherder.setdefault('symbol', _generate_treeherder_symbol(
                 is_nightly, build_platform
             ))
 
-            # ccov and msvc builds are tier 2, so they cannot have tier 1 tasks
+            # ccov builds are tier 2, so they cannot have tier 1 tasks
             # depending on them.
             treeherder.setdefault(
                 'tier',
                 dep_job.task.get('extra', {}).get('treeherder', {}).get('tier', 1)
             )
             treeherder.setdefault('kind', 'build')
 
         label = job['label']