diff --git a/ganttzk/src/main/java/org/zkoss/ganttz/timetracker/TimeTracker.java b/ganttzk/src/main/java/org/zkoss/ganttz/timetracker/TimeTracker.java
index 9eaaaffa4..5f684ae53 100644
--- a/ganttzk/src/main/java/org/zkoss/ganttz/timetracker/TimeTracker.java
+++ b/ganttzk/src/main/java/org/zkoss/ganttz/timetracker/TimeTracker.java
@@ -178,11 +178,11 @@ public class TimeTracker {
         Date newStart = interval.getStart();
         Date newFinish = interval.getFinish();
         boolean changed = false;
-        if (getRealInterval().getStart().compareTo(startMinusOneYear(task)) > 0) {
+        if (interval.getStart().compareTo(startMinusOneYear(task)) > 0) {
             newStart = startMinusOneYear(task);
             changed = true;
         }
-        if (getRealInterval().getFinish()
+        if (interval.getFinish()
                 .compareTo(endPlusOneYear(task)) < 0) {
             newFinish = endPlusOneYear(task);
             changed = true;