diff --git a/src/perl/Build.PL b/src/perl/Build.PL
index 9e6838aac..3bdc00b4a 100644
--- a/src/perl/Build.PL
+++ b/src/perl/Build.PL
@@ -22,11 +22,12 @@ my $build = Build->new
                           'Module::Build'   => 0.42
                          },
    test_requires      => {
-                          'TAP::Harness'    => '>= 3.30',
-                          'Test::Class'     => '>= 0.41',
-                          'Test::More'      => '>= 0.98',
-                          'Test::Exception' => '>= 0.32',
-                          'Test::Compile'   => 0
+                          'TAP::Harness'     => '>= 3.30',
+                          'Test::Class'      => '>= 0.41',
+                          'Test::MockObject' => 0,
+                          'Test::More'       => '>= 0.98',
+                          'Test::Exception'  => '>= 0.32',
+                          'Test::Compile'    => 0
                          },
    requires          => {
                          'Config::IniFiles'                    => '>= 2.8.6',
diff --git a/src/perl/lib/WTSI/NPG/Genotyping/Database/Infinium.pm b/src/perl/lib/WTSI/NPG/Genotyping/Database/Infinium.pm
index 95aad14dc..37632e926 100644
--- a/src/perl/lib/WTSI/NPG/Genotyping/Database/Infinium.pm
+++ b/src/perl/lib/WTSI/NPG/Genotyping/Database/Infinium.pm
@@ -384,7 +384,7 @@ sub find_called_file_project {
                  idat_grn_path     => <path string of IDAT format result file>,
                  idat_red_path     => <path string of IDAT format result file>,
                  image_date        => <Imaging date, DB native format>,
-                 iso_image_date    => <Imaging date, ISO8601 format> }
+                 image_iso_date    => <Imaging date, ISO8601 format> }
 
                 The finds all samples in a project, even those that have
                 never been scanned. For those that have been scanned more than
@@ -520,7 +520,7 @@ sub find_project_samples {
                  idat_grn_path     => <path string of IDAT format result file>,
                  idat_red_path     => <path string of IDAT format result file>,
                  image_date        => <Imaging date, DB native format>,
-                 iso_image_date    => <Imaging date, ISO8601 format>}
+                 image_iso_date    => <Imaging date, ISO8601 format>}
  Returntype : hashref
 
 =cut
@@ -625,7 +625,7 @@ sub find_project_completed_samples {
                  idat_grn_path     => <path string of IDAT format result file>,
                  idat_red_path     => <path string of IDAT format result file>,
                  image_date        => <Imaging date, DB native format>,
-                 iso_image_date    => <Imaging date, ISO8601 format>}
+                 image_iso_date    => <Imaging date, ISO8601 format>}
  Returntype : hashref
 
 =cut
@@ -679,7 +679,7 @@ sub find_scanned_sample {
                  idat_grn_path     => <path string of IDAT format result file>,
                  idat_red_path     => <path string of IDAT format result file>,
                  image_date        => <Imaging date, DB native format>,
-                 iso_image_date    => <Imaging date, ISO8601 format>}
+                 image_iso_date    => <Imaging date, ISO8601 format>}
   Returntype : hashref
 
 =cut
@@ -915,10 +915,10 @@ sub _choose_from_scans {
 
   foreach my $sample (@$samples) {
     my $name = $sample->{sample};
-    push @sample_names, $name;
 
     unless (exists $samples_by_name{$name}) {
       $samples_by_name{$name} = [];
+      push @sample_names, $name;
     }
 
     push @{$samples_by_name{$name}}, $sample;
diff --git a/src/perl/t/WTSI/NPG/Genotyping/Database/InfiniumTest.pm b/src/perl/t/WTSI/NPG/Genotyping/Database/InfiniumTest.pm
index a84d515eb..51f5db5a2 100644
--- a/src/perl/t/WTSI/NPG/Genotyping/Database/InfiniumTest.pm
+++ b/src/perl/t/WTSI/NPG/Genotyping/Database/InfiniumTest.pm
@@ -7,8 +7,9 @@ use strict;
 use warnings;
 
 use base qw(WTSI::NPG::Test);
-use Test::More tests => 13;
+use Test::More tests => 14;
 use Test::Exception;
+use Test::MockObject;
 
 use Log::Log4perl;
 
@@ -60,4 +61,84 @@ sub disconnect : Test(4) {
   }
 }
 
+sub repeat_scans : Test(1) {
+
+  my $db = WTSI::NPG::Genotyping::Database::Infinium->new
+    (name    => 'infinium',
+     inifile => $db_credentials);
+
+  # This test is fragile because it relies on knowing about the
+  # internals of the package under test. However, it's better than
+  # nothing, until we commit resources to refactoring.
+  my $sth = Test::MockObject->new;
+  $sth->set_true('execute');
+  $sth->set_series('fetchrow_hashref',
+                   {plate             => 'ABC123456-DNA',
+                    well              => 'A01',
+                    sample            => 'sample1',
+                    beadchip          => '0123456789',
+                    beadchip_section  => 'R01C01',
+                    beadchip_design   => 'test_design',
+                    beadchip_revision => '1',
+                    status            => 'Pass',
+                    gtc_file          => 'test.gtc',
+                    idat_grn_file     => 'test_Grn.idat',
+                    idat_red_file     => 'test_Red.idat',
+                    idat_grn_path     => '/test',
+                    idat_red_path     => '/test',
+                    image_date        => '',
+                    image_iso_date    => '2016-10-01'},
+                   {plate             => 'ABC123456-DNA',
+                    well              => 'A01',
+                    sample            => 'sample1',
+                    beadchip          => '0123456789',
+                    beadchip_section  => 'R01C01',
+                    beadchip_design   => 'test_design',
+                    beadchip_revision => '1',
+                    status            => 'Pass',
+                    gtc_file          => 'test.gtc',
+                    idat_grn_file     => 'test_Grn.idat',
+                    idat_red_file     => 'test_Red.idat',
+                    idat_grn_path     => '/test',
+                    idat_red_path     => '/test',
+                    image_date        => '',
+                    image_iso_date    => '2016-10-02'},
+                   {plate             => 'ABC123456-DNA',
+                    well              => 'A01',
+                    sample            => 'sample1',
+                    beadchip          => '0123456789',
+                    beadchip_section  => 'R01C01',
+                    beadchip_design   => 'test_design',
+                    beadchip_revision => '1',
+                    status            => 'Pass',
+                    gtc_file          => 'test.gtc',
+                    idat_grn_file     => 'test_Grn.idat',
+                    idat_red_file     => 'test_Red.idat',
+                    idat_grn_path     => '/test',
+                    idat_red_path     => '/test',
+                    image_date        => '',
+                    image_iso_date    => '2016-10-03'});
+
+  my $dbh = Test::MockObject->new;
+  $dbh->set_always('prepare', $sth);
+  $db->dbh($dbh);
+
+  is_deeply($db->find_project_samples('test'),
+            [{plate             => 'ABC123456-DNA',
+              well              => 'A01',
+              sample            => 'sample1',
+              beadchip          => '0123456789',
+              beadchip_section  => 'R01C01',
+              beadchip_design   => 'test_design',
+              beadchip_revision => '1',
+              status            => 'Pass',
+              gtc_file          => 'test.gtc',
+              idat_grn_file     => 'test_Grn.idat',
+              idat_red_file     => 'test_Red.idat',
+              idat_grn_path     => '/test',
+               idat_red_path     => '/test',
+              image_date        => '',
+              image_iso_date    => '2016-10-03'}],
+             'Repeat scans resolved to latest');
+}
 1;