diff --git a/htdocs/ViewSchedule.vue b/htdocs/ViewSchedule.vue
index 960f176..a22c94a 100644
--- a/htdocs/ViewSchedule.vue
+++ b/htdocs/ViewSchedule.vue
@@ -1,5 +1,8 @@
 <template>
-	<div v-if="(age === undefined) || (age > 0)" class="alert alert-warning">⚠ update error<template v-if="age >= 90000">; last updated {{Math.round(age/60000)}} minutes ago</template></div>
+	<template v-if="age !== undefined">
+		<div v-if="age == Infinity" class="alert alert-danger">❌ update error</div>
+		<div v-else-if="age >= 90000" class="alert alert-warning">⚠ last updated <template v-if="age < 3600000">{{ts.toLocaleString()}}</template><template v-else>{{ts.toLocaleString()}}</template></div>
+	</template>
 	<table class="table" style="font-family: monospace;" v-if="appointments && appointments.length > 0">
 		<thead>
 			<tr><th style="width: 7rem;">Time</th><th>Clinic</th><th>Patient</th><th>Note</th><th style="width: 16rem;">Assignee</th></tr>
@@ -71,7 +74,7 @@
 			return {
 				appointments: [],
 				ts: null,
-				age: 0
+				age: undefined
 			};
 		},
 		computed: {
@@ -87,11 +90,14 @@
 			async update() {
 				try {
 					this.appointments = (await this.client.SDEC_CRSCHED(this.selection.join('|') + '|', strfdate_vista(this.date_begin), strfdate_vista(this.date_end) + '@2359')).sort((a, b) => (new Date(a.START_TIME)) - (new Date(b.START_TIME)));
-					this.ts = new Date();
-					this.age = 0;
+					var now = new Date();
+					this.ts = this.appointments._ts ? new Date(1000*this.appointments._ts) : now;
+					this.age = now - this.ts;
+					this.timer = window.setTimeout(this.update, Math.max(60000 - this.age, 10000));
 				} catch(ex) {
-					this.age = this.ts ? (new Date()) - this.ts : undefined;
+					this.age = this.ts ? (new Date()) - this.ts : Infinity;
 					console.warn(ex);
+					this.timer = window.setTimeout(this.update, 30000);
 				}
 			}
 		},
@@ -99,14 +105,13 @@
 			this.$watch(
 				() => (this.client, this.selection, this.date_begin, this.date_end, {}),
 				debounce(async () => {
-					window.clearInterval(this.timer);
+					window.clearTimeout(this.timer);
 					this.update();
-					this.timer = window.setInterval(this.update, 60000);
 				}, 500)
 			);
 		},
 		unmounted() {
-			window.clearInterval(this.timer);
+			window.clearTimeout(this.timer);
 		}
 	};
 </script>