diff --git a/htdocs/RoutePatientReports.vue b/htdocs/RoutePatientReports.vue
index f23ad50..e1da7b4 100644
--- a/htdocs/RoutePatientReports.vue
+++ b/htdocs/RoutePatientReports.vue
@@ -292,7 +292,13 @@
 	}
 
 	function data_endtime(data) {
-		for(var i = data.length - 1; i >= 0; --i) if((data[i].time) && (!isNaN(data[i].time))) return data[i].time;
+		for(var i = data.length - 1, time; i >= 0; --i) if((time = data[i].time) && (!isNaN(time))) return time;
+	}
+
+	function data_endtime_conservative(data) {
+		var dt_end = data_endtime(data);
+		if(dt_end) for(var i = data.length - 1, time; i >= 0; --i) if((time = data[i].time) && (time > dt_end)) return time;
+		return dt_end;
 	}
 
 	function data_interval(data) {
@@ -388,8 +394,7 @@
 			} else var res = [];
 			if(hasmore) {	// lookahead
 				var batch = (await client.ORWRP_REPORT_TEXT_LONGCACHE(dfn, rpt_id, '', SZ_RANGE, '', -1, cursor.toFixed(9))).map(fn_map).sort((a, b) => b.time - a.time);
-				res.dt_next = data_endtime(batch);
-				if(res.dt_next) res.next = strftime_vista(res.dt_next);
+				if(res.dt_next = (batch.length >= SZ_WINDOW ? data_endtime_conservative : data_endtime)(batch)) res.next = strftime_vista(res.dt_next);
 			}
 			if((!res.dt_next) && (cursor) && (data.length > 0) && ((res.length < 1) || (res[res.length - 1] !== data[data.length - 1]))) res.dt_next = strptime_vista(res.next = cursor);
 			return res;