diff --git a/lib/WeBWorK/AchievementItems/ReducedCred.pm b/lib/WeBWorK/AchievementItems/ReducedCred.pm
index 089dbfe410..ee77b15ac3 100644
--- a/lib/WeBWorK/AchievementItems/ReducedCred.pm
+++ b/lib/WeBWorK/AchievementItems/ReducedCred.pm
@@ -20,9 +20,11 @@ use Mojo::Base 'WeBWorK::AchievementItems', -signatures;
 # Reduced scoring needs to be enabled for this item to work.
 
 use WeBWorK::Utils qw(x nfreeze_base64 thaw_base64);
-use WeBWorK::Utils::DateTime qw(between);
+use WeBWorK::Utils::DateTime qw(after between);
 use WeBWorK::Utils::Sets qw(format_set_name_display);
 
+use constant ONE_DAY => 86400;
+
 sub new ($class) {
 	return bless {
 		id          => 'ReducedCred',
@@ -39,7 +41,8 @@ sub print_form ($self, $sets, $setProblemIds, $c) {
 
 	for my $i (0 .. $#$sets) {
 		push(@openSets, [ format_set_name_display($sets->[$i]->set_id) => $sets->[$i]->set_id ])
-			if (between($sets->[$i]->open_date, $sets->[$i]->due_date) && $sets->[$i]->assignment_type eq 'default');
+			if (between($sets->[$i]->open_date, $sets->[$i]->due_date + ONE_DAY())
+				&& $sets->[$i]->assignment_type eq 'default');
 	}
 
 	return unless @openSets;
@@ -79,12 +82,24 @@ sub use_item ($self, $userName, $c) {
 	my $userSet = $db->getUserSet($userName, $setID);
 	return "Couldn't find that set!" unless $set && $userSet;
 
-	# Enable reduced scoring on the set and add the reduced scoring period to the due date.
-	my $additionalTime = 60 * $ce->{pg}{ansEvalDefaults}{reducedScoringPeriod};
+	# Change the seed for all of the problems if the set is currently closed.
+	if (after($set->due_date)) {
+		my @probIDs = $db->listUserProblems($userName, $setID);
+		for my $probID (@probIDs) {
+			my $problem = $db->getUserProblem($userName, $setID, $probID);
+			$problem->problem_seed($problem->problem_seed + 100);
+			$db->putUserProblem($problem);
+		}
+	}
+
+	# Either there is already a valid reduced scoring date, or set the reduced scoring date to the close date.
+	$userSet->reduced_scoring_date($set->due_date)
+		unless ($set->reduced_scoring_date && ($set->reduced_scoring_date < $set->due_date));
 	$userSet->enable_reduced_scoring(1);
-	$userSet->reduced_scoring_date($set->due_date());
-	$userSet->due_date($set->due_date() + $additionalTime);
-	$userSet->answer_date($set->answer_date() + $additionalTime);
+	# Add time to the close date
+	$userSet->due_date($set->due_date + ONE_DAY());
+	# This may require also extending the answer date.
+	$userSet->answer_date($userSet->due_date) if ($userSet->due_date > $set->answer_date);
 	$db->putUserSet($userSet);
 
 	$globalData->{ $self->{id} }--;