Index: lams_monitoring/src/java/org/lamsfoundation/lams/monitoring/service/MonitoringService.java
===================================================================
diff -u -r7913826df20868a8bf035076a14ac89d5e615b46 -r33c320461eb25493b3c38170ec23291cb0d953c6
--- lams_monitoring/src/java/org/lamsfoundation/lams/monitoring/service/MonitoringService.java	(.../MonitoringService.java)	(revision 7913826df20868a8bf035076a14ac89d5e615b46)
+++ lams_monitoring/src/java/org/lamsfoundation/lams/monitoring/service/MonitoringService.java	(.../MonitoringService.java)	(revision 33c320461eb25493b3c38170ec23291cb0d953c6)
@@ -848,6 +848,11 @@
 		// work out new offset in minutes from lesson start time to the given date
 		Lesson lesson = learnerService.getLessonByActivity(gate);
 		Date lessonStartingTime = lesson.getStartDateTime();
+		if (lessonStartingTime == null && Lesson.NOT_STARTED_STATE.equals(lesson.getLessonStateId())) {
+		    // Assume the lesson will start at the scheduled time
+		    lessonStartingTime = lesson.getScheduleStartDate();
+		}
+
 		if (lessonStartingTime != null) {
 		    // Should never be null, so just skip that case. If it was null how did the initial trigger get set up?
 		    long offset = (tzSchedulingDatetime.getTime() - lessonStartingTime.getTime()) / 60000;
@@ -892,6 +897,11 @@
 			gate.setGateStartTimeOffset(offset);
 			activityDAO.update(gate);
 		    }
+		} else {
+		    log.error(new StringBuilder(
+			    "Unable to reschedule gate opening time as we are missing the lesson starting time. Schedule gate ")
+				    .append(gate).append(" lesson ").append(lesson.getLessonId()).append(" status ")
+				    .append(lesson.getLessonStateId()).toString());
 		}
 	    }
 	}
Index: lams_monitoring/src/java/org/lamsfoundation/lams/monitoring/web/GateAction.java
===================================================================
diff -u -r7913826df20868a8bf035076a14ac89d5e615b46 -r33c320461eb25493b3c38170ec23291cb0d953c6
--- lams_monitoring/src/java/org/lamsfoundation/lams/monitoring/web/GateAction.java	(.../GateAction.java)	(revision 7913826df20868a8bf035076a14ac89d5e615b46)
+++ lams_monitoring/src/java/org/lamsfoundation/lams/monitoring/web/GateAction.java	(.../GateAction.java)	(revision 33c320461eb25493b3c38170ec23291cb0d953c6)
@@ -29,6 +29,7 @@
 import java.text.SimpleDateFormat;
 import java.util.Calendar;
 import java.util.Collection;
+import java.util.Date;
 import java.util.GregorianCalendar;
 import java.util.HashSet;
 import java.util.LinkedList;
@@ -354,9 +355,22 @@
 	    learnerService = MonitoringServiceProxy.getLearnerService(getServlet().getServletContext());
 	    Lesson lesson = learnerService.getLessonByActivity(scheduleGate);
 	    Calendar startingTime = new GregorianCalendar(TimeZone.getDefault());
-	    startingTime.setTime(lesson.getStartDateTime());
-	    startingTime.add(Calendar.MINUTE, scheduleGate.getGateStartTimeOffset().intValue());
-	    gateForm.set("startingTime", startingTime.getTime());
+	    Date lessonStartTime = lesson.getStartDateTime();
+	    if (lessonStartTime == null && Lesson.NOT_STARTED_STATE.equals(lesson.getLessonStateId())) {
+		// Assume the lesson will start at the scheduled time
+		lessonStartTime = lesson.getScheduleStartDate();
+	    }
+	    if (lessonStartTime != null) {
+		startingTime.setTime(lessonStartTime);
+		startingTime.add(Calendar.MINUTE, scheduleGate.getGateStartTimeOffset().intValue());
+		gateForm.set("startingTime", startingTime.getTime());
+	    } else {
+		log.error(new StringBuilder(
+			"Unable to calculate schedule gate opening time as we are missing the lesson starting time. Schedule gate ")
+				.append(scheduleGate).append(" lesson ").append(lesson.getLessonId()).append(" status ")
+				.append(lesson.getLessonStateId()).toString());
+		gateForm.set("startingTime", null);
+	    }
 	}
 
 	return mapping.findForward(GateAction.VIEW_SCHEDULE_GATE);
Index: lams_monitoring/web/gate/scheduleGateContent.jsp
===================================================================
diff -u -r225d293907a5e2976e367ee3aa790239bad38699 -r33c320461eb25493b3c38170ec23291cb0d953c6
--- lams_monitoring/web/gate/scheduleGateContent.jsp	(.../scheduleGateContent.jsp)	(revision 225d293907a5e2976e367ee3aa790239bad38699)
+++ lams_monitoring/web/gate/scheduleGateContent.jsp	(.../scheduleGateContent.jsp)	(revision 33c320461eb25493b3c38170ec23291cb0d953c6)
@@ -86,7 +86,7 @@
 			</c:when>
 			<c:otherwise>
 				<c:if test="${not GateForm.map.gate.gateOpen}" >
-					<p><fmt:message key="label.schedule.gate.open.message"/> <lams:Date value="${GateForm.map.startingTime}"/></p>
+					<p><fmt:message key="label.schedule.gate.open.message"/>&nbsp;<lams:Date value="${GateForm.map.startingTime}"/></p>
 					
 					<html:form action="/gate?method=scheduleGate" target="_self" styleClass="form-inline">
 					<input type="hidden" name="activityId" value="${GateForm.map.activityId}" />