diff --git a/metricflow-semantics/metricflow_semantics/specs/time_dimension_spec.py b/metricflow-semantics/metricflow_semantics/specs/time_dimension_spec.py
index 3aec625a22..f6957e8fd7 100644
--- a/metricflow-semantics/metricflow_semantics/specs/time_dimension_spec.py
+++ b/metricflow-semantics/metricflow_semantics/specs/time_dimension_spec.py
@@ -154,7 +154,6 @@ def with_grain(self, time_granularity: ExpandedTimeGranularity) -> TimeDimension
             aggregation_state=self.aggregation_state,
         )
 
-    @property
     def with_base_grain(self) -> TimeDimensionSpec:  # noqa: D102
         return TimeDimensionSpec(
             element_name=self.element_name,
diff --git a/metricflow/dataflow/builder/dataflow_plan_builder.py b/metricflow/dataflow/builder/dataflow_plan_builder.py
index d98bcd4eae..22c381a039 100644
--- a/metricflow/dataflow/builder/dataflow_plan_builder.py
+++ b/metricflow/dataflow/builder/dataflow_plan_builder.py
@@ -798,7 +798,9 @@ def _build_plan_for_distinct_values(
 
         for time_dimension_spec in required_linkable_specs.time_dimension_specs:
             if time_dimension_spec.time_granularity.is_custom_granularity:
-                include_base_grain = time_dimension_spec.with_base_grain in required_linkable_specs.time_dimension_specs
+                include_base_grain = (
+                    time_dimension_spec.with_base_grain() in required_linkable_specs.time_dimension_specs
+                )
                 output_node = JoinToCustomGranularityNode.create(
                     parent_node=output_node,
                     time_dimension_spec=time_dimension_spec,
@@ -1572,7 +1574,9 @@ def _build_aggregated_measure_from_measure_source_node(
 
         for time_dimension_spec in queried_linkable_specs.time_dimension_specs:
             if time_dimension_spec.time_granularity.is_custom_granularity:
-                include_base_grain = time_dimension_spec.with_base_grain in required_linkable_specs.time_dimension_specs
+                include_base_grain = (
+                    time_dimension_spec.with_base_grain() in required_linkable_specs.time_dimension_specs
+                )
                 unaggregated_measure_node = JoinToCustomGranularityNode.create(
                     parent_node=unaggregated_measure_node,
                     time_dimension_spec=time_dimension_spec,
diff --git a/metricflow/dataflow/builder/node_evaluator.py b/metricflow/dataflow/builder/node_evaluator.py
index f651e06de5..6b365cc09f 100644
--- a/metricflow/dataflow/builder/node_evaluator.py
+++ b/metricflow/dataflow/builder/node_evaluator.py
@@ -409,7 +409,7 @@ def evaluate_node(
         data_set_linkable_specs = candidate_spec_set.linkable_specs
         # Look for which nodes can satisfy the linkable specs at their base grains. Custom grains will be joined later.
         required_linkable_specs_with_base_grains = [
-            spec.with_base_grain if isinstance(spec, TimeDimensionSpec) else spec for spec in required_linkable_specs
+            spec.with_base_grain() if isinstance(spec, TimeDimensionSpec) else spec for spec in required_linkable_specs
         ]
 
         # These are linkable specs in the start node data set. Those are considered "local".
diff --git a/metricflow/plan_conversion/dataflow_to_sql.py b/metricflow/plan_conversion/dataflow_to_sql.py
index 51276297c9..d3041bee2c 100644
--- a/metricflow/plan_conversion/dataflow_to_sql.py
+++ b/metricflow/plan_conversion/dataflow_to_sql.py
@@ -1436,7 +1436,7 @@ def visit_join_to_custom_granularity_node(self, node: JoinToCustomGranularityNod
         parent_alias = parent_data_set.checked_sql_select_node.from_source_alias
         parent_time_dimension_instance: Optional[TimeDimensionInstance] = None
         for instance in parent_data_set.instance_set.time_dimension_instances:
-            if instance.spec == node.time_dimension_spec.with_base_grain:
+            if instance.spec == node.time_dimension_spec.with_base_grain():
                 parent_time_dimension_instance = instance
                 break
         assert parent_time_dimension_instance, (