diff --git a/lib/WeBWorK/AchievementItems/ExtendDueDate.pm b/lib/WeBWorK/AchievementItems/ExtendDueDate.pm
index f20aba7474..f645c59734 100644
--- a/lib/WeBWorK/AchievementItems/ExtendDueDate.pm
+++ b/lib/WeBWorK/AchievementItems/ExtendDueDate.pm
@@ -19,14 +19,19 @@ use Mojo::Base 'WeBWorK::AchievementItems', -signatures;
 # Item to extend a close date by 24 hours.
 
 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          => 'ExtendDueDate',
 		name        => x('Tunic of Extension'),
-		description => x('Adds 24 hours to the close date of a homework.')
+		description => x(
+			'Adds 24 hours to the close date of a homework. '
+				. 'This will randomize problem details if used after the original close date.'
+		)
 	}, $class;
 }
 
@@ -35,7 +40,8 @@ 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;
@@ -71,10 +77,20 @@ sub use_item ($self, $userName, $c) {
 	my $userSet = $db->getUserSet($userName, $setID);
 	return q{Couldn't find that set!} unless $set && $userSet;
 
-	# Add time to the reduced scoring date, due date, and answer date.
-	$userSet->reduced_scoring_date($set->reduced_scoring_date() + 86400) if $set->reduced_scoring_date;
-	$userSet->due_date($set->due_date() + 86400);
-	$userSet->answer_date($set->answer_date() + 86400);
+	# Change the seed for all of the problems if the set is currently closed.
+	if (after($set->due_date)) {
+		for my $problem ($db->getUserProblemsWhere({ user_id => $userName, set_id => $setID })) {
+			$problem->problem_seed($problem->problem_seed % 2**31 + 1);
+			$db->putUserProblem($problem);
+		}
+	}
+
+	# Add time to the reduced scoring date if it was defined in the first place
+	$userSet->reduced_scoring_date($set->reduced_scoring_date + ONE_DAY) if $set->reduced_scoring_date;
+	# 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} }--;
diff --git a/lib/WeBWorK/AchievementItems/ExtendDueDateGW.pm b/lib/WeBWorK/AchievementItems/ExtendDueDateGW.pm
index 3d99f661f7..cccefc6f12 100644
--- a/lib/WeBWorK/AchievementItems/ExtendDueDateGW.pm
+++ b/lib/WeBWorK/AchievementItems/ExtendDueDateGW.pm
@@ -22,6 +22,8 @@ use WeBWorK::Utils           qw(x nfreeze_base64 thaw_base64);
 use WeBWorK::Utils::DateTime qw(between);
 use WeBWorK::Utils::Sets     qw(format_set_name_display);
 
+use constant ONE_DAY => 86400;
+
 sub new ($class) {
 	return bless {
 		id          => 'ExtendDueDateGW',
@@ -78,10 +80,10 @@ sub use_item ($self, $userName, $c) {
 	return q{Couldn't find that set!} unless $set && $userSet;
 
 	# Add time to the reduced scoring date, due date, and answer date.
-	$userSet->reduced_scoring_date($set->reduced_scoring_date() + 86400)
+	$userSet->reduced_scoring_date($set->reduced_scoring_date() + ONE_DAY)
 		if defined($set->reduced_scoring_date()) && $set->reduced_scoring_date();
-	$userSet->due_date($set->due_date() + 86400);
-	$userSet->answer_date($set->answer_date() + 86400);
+	$userSet->due_date($set->due_date() + ONE_DAY);
+	$userSet->answer_date($set->answer_date() + ONE_DAY);
 	$db->putUserSet($userSet);
 
 	# Add time to the reduced scoring date, due date, and answer date for all versions.
@@ -89,10 +91,10 @@ sub use_item ($self, $userName, $c) {
 
 	for my $version (@versions) {
 		$set = $db->getSetVersion($userName, $setID, $version);
-		$set->reduced_scoring_date($set->reduced_scoring_date() + 86400)
+		$set->reduced_scoring_date($set->reduced_scoring_date() + ONE_DAY)
 			if defined($set->reduced_scoring_date()) && $set->reduced_scoring_date();
-		$set->due_date($set->due_date() + 86400);
-		$set->answer_date($set->answer_date() + 86400);
+		$set->due_date($set->due_date() + ONE_DAY);
+		$set->answer_date($set->answer_date() + ONE_DAY);
 		$db->putSetVersion($set);
 	}
 
diff --git a/lib/WeBWorK/AchievementItems/ReducedCred.pm b/lib/WeBWorK/AchievementItems/ReducedCred.pm
index 9ff714ecb8..297c275d7e 100644
--- a/lib/WeBWorK/AchievementItems/ReducedCred.pm
+++ b/lib/WeBWorK/AchievementItems/ReducedCred.pm
@@ -20,16 +20,19 @@ 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',
 		name        => x('Ring of Reduction'),
 		description => x(
 			'Enable reduced scoring for a homework set.  This will allow you to submit answers '
-				. 'for partial credit for 24 hours after the close date.'
+				. 'for partial credit for 24 hours after the close date. '
+				. 'This will randomize problem details if used after the original close date.'
 		)
 	}, $class;
 }
@@ -39,7 +42,8 @@ sub print_form ($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 +83,22 @@ 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)) {
+		for my $problem ($db->getUserProblemsWhere({ user_id => $userName, set_id => $setID })) {
+			$problem->problem_seed($problem->problem_seed % 2**31 + 1);
+			$db->putUserProblem($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} }--;
diff --git a/lib/WeBWorK/AchievementItems/SuperExtendDueDate.pm b/lib/WeBWorK/AchievementItems/SuperExtendDueDate.pm
index 28ee31a660..ccf960321d 100644
--- a/lib/WeBWorK/AchievementItems/SuperExtendDueDate.pm
+++ b/lib/WeBWorK/AchievementItems/SuperExtendDueDate.pm
@@ -19,14 +19,19 @@ use Mojo::Base 'WeBWorK::AchievementItems', -signatures;
 # Item to extend a close date by 48 hours.
 
 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 TWO_DAYS => 172800;
+
 sub new ($class) {
 	return bless {
 		id          => 'SuperExtendDueDate',
 		name        => x('Robe of Longevity'),
-		description => x('Adds 48 hours to the close date of a homework.')
+		description => x(
+			'Adds 48 hours to the close date of a homework. '
+				. 'This will randomize problem details if used after the original close date.'
+		)
 	}, $class;
 }
 
@@ -35,7 +40,8 @@ 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 + TWO_DAYS)
+				&& $sets->[$i]->assignment_type eq 'default');
 	}
 
 	return unless @openSets;
@@ -71,10 +77,20 @@ sub use_item ($self, $userName, $c) {
 	my $userSet = $db->getUserSet($userName, $setID);
 	return q{Couldn't find that set!} unless $set && $userSet;
 
-	# Add time to the reduced scoring date, due date, and answer date.
-	$userSet->reduced_scoring_date($set->reduced_scoring_date() + 172800) if $set->reduced_scoring_date;
-	$userSet->due_date($set->due_date() + 172800);
-	$userSet->answer_date($set->answer_date() + 172800);
+	# Change the seed for all of the problems if the set is currently closed.
+	if (after($set->due_date)) {
+		for my $problem ($db->getUserProblemsWhere({ user_id => $userName, set_id => $setID })) {
+			$problem->problem_seed($problem->problem_seed % 2**31 + 1);
+			$db->putUserProblem($problem);
+		}
+	}
+
+	# Add time to the reduced scoring date if it was defined in the first place
+	$userSet->reduced_scoring_date($set->reduced_scoring_date + TWO_DAYS) if $set->reduced_scoring_date;
+	# Add time to the close date
+	$userSet->due_date($set->due_date + TWO_DAYS);
+	# 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} }--;