diff --git a/TrioTests/BolusCalculatorTests/BolusCalculatorTests.swift b/TrioTests/BolusCalculatorTests/BolusCalculatorTests.swift
index 9e75fbb53..81492fee1 100644
--- a/TrioTests/BolusCalculatorTests/BolusCalculatorTests.swift
+++ b/TrioTests/BolusCalculatorTests/BolusCalculatorTests.swift
@@ -867,8 +867,8 @@ extension BolusCalculatorTests {
     /// - Returns: The current decimal value for the specified setting type
     private func getCurrentSettingValue(for type: SettingType, at date: Date) async -> Decimal {
         let calendar = Calendar.current
-        let midnight = calendar.startOfDay(for: date)
-        let minutesSinceMidnight = calendar.dateComponents([.minute], from: midnight, to: date).minute ?? 0
+        let components = calendar.dateComponents([.hour, .minute], from: date)
+        let minutesSinceMidnight = (components.hour ?? 0) * 60 + (components.minute ?? 0)
 
         switch type {
         case .basal:
diff --git a/TrioTests/CoreDataTests/ScheduledBasalInferenceTests.swift b/TrioTests/CoreDataTests/ScheduledBasalInferenceTests.swift
index 9955ad0e6..7ccc0652b 100644
--- a/TrioTests/CoreDataTests/ScheduledBasalInferenceTests.swift
+++ b/TrioTests/CoreDataTests/ScheduledBasalInferenceTests.swift
@@ -14,9 +14,10 @@ import Testing
         [BasalProfileEntry(start: "00:00", minutes: 0, rate: 1.0)]
     }
 
-    // startOfDay-anchored so all times share one calendar day, matching the sweep's boundary math
+    // wall-clock anchored so DST transitions don't shift hour/minute semantics
     private func time(_ hour: Int, _ minute: Int = 0) -> Date {
-        Calendar.current.startOfDay(for: Date()).addingTimeInterval(TimeInterval(hour * 3600 + minute * 60))
+        Calendar.current.date(bySettingHour: hour, minute: minute, second: 0, of: Date()) ?? Calendar.current
+            .startOfDay(for: Date())
     }
 
     private func tempBasal(_ start: Date, _ end: Date) -> TimelineEvent {