diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index d8d87daf..2d73afd6 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -59,7 +59,7 @@ jobs:
           miniforge-version: latest
           mamba-version: "*"
           activate-environment: pymc-experimental-test
-          channel-priority: strict
+          channel-priority: true
           environment-file: conda-envs/environment-test.yml
           python-version: ${{matrix.python-version}}
           use-mamba: true
@@ -124,7 +124,7 @@ jobs:
           miniforge-version: latest
           mamba-version: "*"
           activate-environment: pymc-experimental-test
-          channel-priority: strict
+          channel-priority: true
           environment-file: conda-envs/windows-environment-test.yml
           python-version: ${{matrix.python-version}}
           use-mamba: true
diff --git a/conda-envs/environment-test.yml b/conda-envs/environment-test.yml
index 6e8b6b48..6c57d5ae 100644
--- a/conda-envs/environment-test.yml
+++ b/conda-envs/environment-test.yml
@@ -1,13 +1,13 @@
 name: pymc-experimental-test
 channels:
 - conda-forge
-- defaults
+- nodefaults
 dependencies:
 - pip
+- pymc>=5.1.2
 - pytest-cov>=2.5
 - pytest>=3.0
 - dask
 - xhistogram
 - pip:
-  - pymc>=5.1.2  # CI was failing to resolve
   - blackjax
diff --git a/conda-envs/windows-environment-test.yml b/conda-envs/windows-environment-test.yml
index e179b7a9..0a5d813a 100644
--- a/conda-envs/windows-environment-test.yml
+++ b/conda-envs/windows-environment-test.yml
@@ -1,12 +1,11 @@
 name: pymc-experimental-test
 channels:
 - conda-forge
-- defaults
+- nodefaults
 dependencies:
 - pip
+- pymc>=5.1.2
 - pytest-cov>=2.5
 - pytest>=3.0
 - dask
 - xhistogram
-- pip:
-  - pymc>=5.1.2  # CI was failing to resolve