diff --git a/docs/prune-simulator/prune-simulator_source.js b/docs/prune-simulator/prune-simulator_source.js
index 06e312805..15a2556fc 100644
--- a/docs/prune-simulator/prune-simulator_source.js
+++ b/docs/prune-simulator/prune-simulator_source.js
@@ -735,7 +735,7 @@ Ext.onReady(function() {
 						    if (!self.isValid()) {
 							return;
 						    }
-						    const date = me.getViewModel().get('now');
+						    let date = me.getViewModel().get('now');
 						    date.setFullYear(
 							newDate.getFullYear(),
 							newDate.getMonth(),
@@ -759,7 +759,7 @@ Ext.onReady(function() {
 						    if (!self.isValid()) {
 							return;
 						    }
-						    const date = me.getViewModel().get('now');
+						    let date = me.getViewModel().get('now');
 						    date.setHours(time.getHours());
 						    date.setMinutes(time.getMinutes());
 						},