Clean up the GHG FBS yaml methods

bedrock/analysis/electricity/current/diagnostics/year_alignment/year_alignment_bly_e.py

@@ -452,8 +452,9 @@ def render_report(baseline: dict[str, Any], y2017: dict[str, Any]) -> str:
         "",
         "1. `usa_ghg_data_year` Literal excludes 2017 (breaks "
         "`reconciling_data_years/model1.yaml`)",
-        "2. Electricity-disagg eGRID FBS is only defined for 2023/2024 "
-        "(`egrid_fbs_method_for_year`); 2017 has no eGRID-backed FBS",
+        "2. Electricity disaggregation only allows "
+        "(bea_published, 2023|2024) and (nowcast, 2024) on USAConfig; "
+        "2017 is outside that allow-list",
         "3. USEEIO A-scale (`scale_a_matrix_with_useeio_method=True`) returns 2017 "
         "base A and never calls `reanchor_electricity_aq_after_year_scaling`",
         "",

bedrock/transform/allocation/__tests__/test_cornerstone_ghg_fbs_filename.py

@@ -112,13 +112,24 @@ def _download(name: str, _sub: str, pth: str) -> None:
     assert loaded['marker'].tolist() == [newer]
 
 
-def test_pin_for_a_different_stem_raises(monkeypatch: pytest.MonkeyPatch) -> None:
+def test_pin_wins_when_stem_differs_from_selected_base_name(
+    tmp_path: Path, monkeypatch: pytest.MonkeyPatch
+) -> None:
+    """Historical pins may use a retired stem while selection is year-only."""
     name = 'GHG_national_Cornerstone_nowcast_facilities_2024_v0.3.0_3a1dddc.parquet'
+    _frame('pinned').to_parquet(tmp_path / name)
     monkeypatch.setattr(derived, 'get_usa_config', lambda: _config(name))
-    with pytest.raises(ValueError, match='does not match'):
-        derived._load_cornerstone_ghg_fbs_from_gcs(
-            base_name='GHG_national_Cornerstone_nowcast_facilities_2023'
-        )
+    monkeypatch.setattr('bedrock.utils.config.settings.FBS_DIR', tmp_path)
+
+    def _no_download(*_a: object, **_k: object) -> None:
+        raise AssertionError('pinned file is already local')
+
+    monkeypatch.setattr('bedrock.utils.io.gcp.download_gcs_file', _no_download)
+
+    loaded = derived._load_cornerstone_ghg_fbs_from_gcs(
+        base_name='GHG_national_Cornerstone_2024'
+    )
+    assert loaded['marker'].tolist() == ['pinned']
 
 
 def test_pin_without_a_git_hash_raises(monkeypatch: pytest.MonkeyPatch) -> None: