diff --git a/CHANGELOG.md b/CHANGELOG.md
index aef3a338..fcbe3756 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Changed
 
 - UI Updates for the integrations page ([#2310](https://github.com/grafana/oncall/pull/2310))
+- Prefer shift start when displaying rotation start value for existing shifts ([#2316](https://github.com/grafana/oncall/pull/2316))
+
+### Fixed
+
+- Fixed minor schedule preview issue missing last day ([#2316](https://github.com/grafana/oncall/pull/2316))
 
 ## v1.2.46 (2023-06-22)
 
diff --git a/grafana-plugin/src/containers/RotationForm/RotationForm.tsx b/grafana-plugin/src/containers/RotationForm/RotationForm.tsx
index df9ac68b..7f818997 100644
--- a/grafana-plugin/src/containers/RotationForm/RotationForm.tsx
+++ b/grafana-plugin/src/containers/RotationForm/RotationForm.tsx
@@ -370,10 +370,11 @@ const RotationForm = observer((props: RotationFormProps) => {
   useEffect(() => {
     if (shift) {
       setRotationName(getShiftName(shift));
-      const rotationStart = getDateTime(shift.rotation_start);
-      setRotationStart(rotationStart);
-      setRotationEnd(shift.until ? getDateTime(shift.until) : getDateTime(shift.shift_start).add(1, 'month'));
       const shiftStart = getDateTime(shift.shift_start);
+      // use shiftStart as rotationStart for existing shifts
+      // (original rotationStart defaulted to the shift creation timestamp)
+      setRotationStart(shiftStart);
+      setRotationEnd(shift.until ? getDateTime(shift.until) : getDateTime(shift.shift_start).add(1, 'month'));
       setShiftStart(shiftStart);
       const shiftEnd = getDateTime(shift.shift_end);
       setShiftEnd(shiftEnd);
diff --git a/grafana-plugin/src/models/schedule/schedule.ts b/grafana-plugin/src/models/schedule/schedule.ts
index c0a9ec48..4071088f 100644
--- a/grafana-plugin/src/models/schedule/schedule.ts
+++ b/grafana-plugin/src/models/schedule/schedule.ts
@@ -252,7 +252,7 @@ export class ScheduleStore extends BaseStore {
     const dayBefore = startMoment.subtract(1, 'day');
 
     const response = await makeRequest(`/oncall_shifts/preview/`, {
-      params: { date: getFromString(dayBefore) },
+      params: { date: getFromString(dayBefore), days: 8 },
       data: { type, schedule: scheduleId, shift_pk: shiftId === 'new' ? undefined : shiftId, ...params },
       method: 'POST',
     });