--- loncom/interface/lonnavmaps.pm	2019/07/27 16:44:31	1.509.2.11
+++ loncom/interface/lonnavmaps.pm	2020/01/16 22:00:10	1.509.2.11.2.1
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # Navigate Maps Handler
 #
-# $Id: lonnavmaps.pm,v 1.509.2.11 2019/07/27 16:44:31 raeburn Exp $
+# $Id: lonnavmaps.pm,v 1.509.2.11.2.1 2020/01/16 22:00:10 raeburn Exp $
 
 #
 # Copyright Michigan State University Board of Trustees
@@ -4814,11 +4814,12 @@ sub duedate {
     my $date;
     my @interval=$self->parmval("interval", $part);
     my $due_date=$self->parmval("duedate", $part);
-    if ($interval[0] =~ /\d+/) {
-       my $first_access=&Apache::lonnet::get_first_access($interval[1],
-                                                          $self->{SYMB});
+    if ($interval[0] =~ /^(\d+)/) {
+        my $timelimit = $1;
+        my $first_access=&Apache::lonnet::get_first_access($interval[1],
+                                                           $self->{SYMB});
 	if (defined($first_access)) {
-           my $interval = $first_access+$interval[0];
+            my $interval = $first_access+$timelimit;
 	    $date = (!$due_date || $interval < $due_date) ? $interval 
                                                           : $due_date;
 	} else {