diff --git a/xCAT-server/lib/perl/xCAT/Template.pm b/xCAT-server/lib/perl/xCAT/Template.pm
index ea45ea0e7..547910e78 100644
--- a/xCAT-server/lib/perl/xCAT/Template.pm
+++ b/xCAT-server/lib/perl/xCAT/Template.pm
@@ -1853,18 +1853,23 @@ sub ubuntu_subiquity_otherpkg_sources
 sub ubuntu_subiquity_uses_deb822_sources
 {
     my ($media_dir) = @_;
-    my $release = ubuntu_subiquity_release($media_dir);
-
-    return 1 if $release =~ m{ubuntu([2-9][4-9]|[3-9][0-9])\.\d+};
-    return 0;
+    return ubuntu_subiquity_release_at_least( $media_dir, '24.0' );
 }
 
 sub ubuntu_subiquity_uses_generated_cdrom_source
 {
     my ($media_dir) = @_;
+    return ubuntu_subiquity_release_at_least( $media_dir, '26.0' );
+}
+
+sub ubuntu_subiquity_release_at_least
+{
+    my ( $media_dir, $minimum ) = @_;
     my $release = ubuntu_subiquity_release($media_dir);
 
-    return 1 if $release =~ m{ubuntu([2-9][6-9]|[3-9][0-9])\.\d+};
+    foreach my $version ( $release =~ m{ubuntu(\d{2}\.\d+)}g ) {
+        return 1 if xCAT::Utils->version_cmp( $version, $minimum ) >= 0;
+    }
     return 0;
 }
 
diff --git a/xCAT-test/unit/ubuntu_subiquity_release_policy.t b/xCAT-test/unit/ubuntu_subiquity_release_policy.t
new file mode 100644
index 000000000..021711f2b
--- /dev/null
+++ b/xCAT-test/unit/ubuntu_subiquity_release_policy.t
@@ -0,0 +1,80 @@
+#!/usr/bin/env perl
+## no critic (NamingConventions::Capitalization, TestingAndDebugging::ProhibitNoWarnings)
+use strict;
+use warnings;
+
+our $VERSION = '1.0';
+
+use FindBin;
+use lib "$FindBin::Bin/../../perl-xCAT";
+use lib "$FindBin::Bin/../../xCAT-server/lib/perl";
+use Test::More;
+
+use xCAT::Template;
+
+{
+
+    package UbuntuSubiquityReleaseTable;
+    sub getNodeAttribs { return { os => 'ubuntu26.04' }; }
+}
+
+my @release_cases = (
+    [ '/install/ubuntu23.10/x86_64',   0, 0, 'Ubuntu 23.10' ],
+    [ '/install/ubuntu24.04/x86_64',   1, 0, 'Ubuntu 24.04' ],
+    [ 'ubuntu25.10',                   1, 0, 'Ubuntu 25.10' ],
+    [ '/install/ubuntu26.04/ppc64le',  1, 1, 'Ubuntu 26.04' ],
+    [ 'ubuntu29.10',                   1, 1, 'Ubuntu 29.10' ],
+    [ 'ubuntu99.04',                   1, 1, 'Ubuntu 99.04' ],
+    [ 'ubuntu100.04',                  0, 0, 'three-digit release year' ],
+    [ '/install/ubuntu24.04.1/x86_64', 1, 0, 'Ubuntu 24.04 point release' ],
+    [ '/install/ubuntu26.04.1/x86_64', 1, 1, 'Ubuntu 26.04 point release' ],
+    [ '/install/debian26.04/x86_64',   0, 0, 'non-Ubuntu release' ],
+    [ '/install/ubuntu26/x86_64', 0, 0, 'release without a minor version' ],
+    [
+        '/install/ubuntu26.x/x86_64', 0, 0,
+        'release with a nonnumeric minor version'
+    ],
+);
+
+foreach my $case (@release_cases) {
+    my ( $release, $uses_deb822, $uses_generated_cdrom, $description ) =
+      @{$case};
+    is( xCAT::Template::ubuntu_subiquity_uses_deb822_sources($release),
+        $uses_deb822, "$description keeps the Deb822 source policy" );
+    is(
+        xCAT::Template::ubuntu_subiquity_uses_generated_cdrom_source($release),
+        $uses_generated_cdrom,
+        "$description keeps the generated cdrom source policy"
+    );
+}
+
+{
+    no warnings 'redefine';
+    local *xCAT::Table::new =
+      sub { return bless {}, 'UbuntuSubiquityReleaseTable'; };
+
+    ok(
+        xCAT::Template::ubuntu_subiquity_uses_deb822_sources(),
+        'nodetype OS fallback selects Deb822 sources'
+    );
+    ok(
+        xCAT::Template::ubuntu_subiquity_uses_generated_cdrom_source(),
+        'nodetype OS fallback selects the generated cdrom source'
+    );
+}
+
+{
+    no warnings 'redefine';
+    local *xCAT::Table::new = sub { return; };
+
+    ok(
+        !xCAT::Template::ubuntu_subiquity_uses_deb822_sources(),
+        'missing nodetype data does not select Deb822 sources'
+    );
+    ok(
+        !xCAT::Template::ubuntu_subiquity_uses_generated_cdrom_source(),
+        'missing nodetype data does not select the generated cdrom source'
+    );
+}
+
+done_testing();