diff --git a/xCAT-test/unit/ubuntu_shared_pkglists.t b/xCAT-test/unit/ubuntu_shared_pkglists.t
index ff1d0092e..3046c3985 100644
--- a/xCAT-test/unit/ubuntu_shared_pkglists.t
+++ b/xCAT-test/unit/ubuntu_shared_pkglists.t
@@ -39,7 +39,8 @@ sub resolved {
 }
 
 # The shared lists keep ntp for the releases that still carry it. aarch64 has no list of its own.
-# The install compute profile gets a 24.04 list of its own next, so it is no longer pinned here.
+# The install compute profile has a 24.04 list of its own, with chrony: the Subiquity template
+# installs chrony and ntp cannot join it in one apt transaction (ubuntu_subiquity_pkglists.t).
 foreach my $case ( [ $install, 'service' ], [ $install, 'kvm' ], [ $netboot, 'compute' ] ) {
     my ( $dir, $profile ) = @$case;
     my ( $file, $p ) = resolved( $dir, $profile, 'ubuntu24.04.4', 'aarch64' );
@@ -47,6 +48,11 @@ foreach my $case ( [ $install, 'service' ], [ $install, 'kvm' ], [ $netboot, 'co
     ok( $p->{ntp}, "... which keeps ntp" );
     ok( !$p->{$_}, "... and no longer names $_" ) for qw(libodbc1 qemu-kvm libvirt-bin);
 }
+{
+    my ( $file, $p ) = resolved( $install, 'compute', 'ubuntu24.04.4', 'aarch64' );
+    is( $file, 'compute.ubuntu24.04.pkglist', 'the install compute profile on 24.04 resolves its own list' );
+    ok( $p->{chrony} && !$p->{ntp}, '... which names chrony and not ntp' );
+}
 ok( packages_in("$install/service.pkglist")->{unixodbc}, 'the shared service list names unixodbc' );
 ok( packages_in("$install/service.pkglist")->{'libdbd-pg-perl'}, '... and the PostgreSQL driver beside the MySQL one' );
 
diff --git a/xCAT-test/unit/ubuntu_subiquity_pkglists.t b/xCAT-test/unit/ubuntu_subiquity_pkglists.t
new file mode 100644
index 000000000..393dee965
--- /dev/null
+++ b/xCAT-test/unit/ubuntu_subiquity_pkglists.t
@@ -0,0 +1,62 @@
+#!/usr/bin/env perl
+use strict;
+use warnings;
+
+use File::Spec;
+use FindBin;
+use Test::More;
+
+use lib "$FindBin::Bin/../../perl-xCAT";
+use lib "$FindBin::Bin/../../xCAT-server/lib/perl";
+use xCAT::Postage;
+use xCAT::SvrUtils;
+
+# The Subiquity autoinstall installs the template's fixed packages and the osimage pkglist in one
+# apt transaction, and the template names chrony. The shared compute.pkglist names ntp for the
+# releases before Subiquity, and on the Subiquity releases ntp pulls ntpsec, which conflicts with
+# chrony, so those releases need their own default list. The lists are resolved the way
+# mkinstall resolves them and their packages are read the way ospkgs reads them.
+
+my $repo     = File::Spec->rel2abs( File::Spec->catdir( $FindBin::Bin, '..', '..' ) );
+my $install  = "$repo/xCAT-server/share/xcat/install/ubuntu";
+my $template = "$install/compute.subiquity.tmpl";
+plan skip_all => 'the Ubuntu install directory is not here' unless -d $install && -f $template;
+
+sub packages_in {
+    my ($path) = @_;
+    return { map { $_ => 1 } grep { length } split /,/, xCAT::Postage::get_pkglist_tex($path) };
+}
+
+sub resolved {
+    my ( $os, $arch ) = @_;
+    return xCAT::SvrUtils->get_pkglist_file_name( $install, 'compute', $os, $arch, $os =~ /^(ubuntu\d+\.\d+)/ ? $1 : $os );
+}
+
+open( my $tfh, '<', $template ) or die "$template: $!";
+my $body = do { local $/; <$tfh> };
+close($tfh);
+my ($block) = $body =~ /^  packages:\n((?:    - .*\n)+)/m;
+my %fixed = map { $_ => 1 } ( $block =~ /^    - ([^#\s]+)$/mg );
+ok( $fixed{chrony}, 'the Subiquity template names chrony among its fixed packages' );
+
+my %time_daemon = map { $_ => 1 } qw(chrony ntp ntpsec);
+foreach my $case ( [ 'ubuntu20.04.6', 'x86_64' ], [ 'ubuntu20.04.6', 'ppc64le' ],
+                   [ 'ubuntu22.04.5', 'x86_64' ], [ 'ubuntu22.04.5', 'ppc64le' ],
+                   [ 'ubuntu24.04.4', 'x86_64' ], [ 'ubuntu24.04.4', 'ppc64le' ], [ 'ubuntu24.04.4', 'riscv64' ],
+                   [ 'ubuntu26.04.1', 'x86_64' ], [ 'ubuntu26.04.1', 'riscv64' ] ) {
+    my ( $os, $arch ) = @$case;
+    my $file = resolved( $os, $arch );
+    ok( $file, "$os $arch resolves a compute pkglist" ) or next;
+    my $packages = packages_in($file);
+    ok( $packages->{chrony}, "$os $arch: the list names chrony, the daemon the template installs" );
+    ok( !$packages->{ntp} && !$packages->{ntpdate}, "$os $arch: ... and not ntp, which would conflict with it" );
+    my @daemons = grep { $time_daemon{$_} } keys %{ { %fixed, %$packages } };
+    is( scalar(@daemons), 1, "$os $arch: the autoinstall transaction carries exactly one time daemon" );
+}
+
+# The releases before Subiquity keep the shared list and its ntp.
+my $legacy = resolved( 'ubuntu16.04.7', 'x86_64' );
+is( $legacy, "$install/compute.pkglist", '16.04 still resolves the shared list' );
+ok( packages_in($legacy)->{ntp}, '... which keeps ntp for the releases where chrony was not the default' );
+
+done_testing();