diff -Nru ubuntu-keyring-2012.05.19/debian/changelog ubuntu-keyring-2012.05.19.1/debian/changelog
--- ubuntu-keyring-2012.05.19/debian/changelog	2012-05-19 01:31:52.000000000 +0000
+++ ubuntu-keyring-2012.05.19.1/debian/changelog	2020-05-29 11:58:19.000000000 +0000
@@ -1,3 +1,10 @@
+ubuntu-keyring (2012.05.19.1) xenial; urgency=medium
+
+  * Add 4096R/991BC93C Ubuntu Archive Automatic Signing Key (2018)
+    <ftpmaster@ubuntu.com> to ubuntu-archive-keyring. LP: #1881278
+
+ -- Dimitri John Ledkov <xnox@ubuntu.com>  Fri, 29 May 2020 12:58:19 +0100
+
 ubuntu-keyring (2012.05.19) quantal; urgency=low
 
   * Add 4096R/C0B21F32 Ubuntu Archive Automatic Signing Key (2012)
diff -Nru ubuntu-keyring-2012.05.19/debian/postrm ubuntu-keyring-2012.05.19.1/debian/postrm
--- ubuntu-keyring-2012.05.19/debian/postrm	1970-01-01 00:00:00.000000000 +0000
+++ ubuntu-keyring-2012.05.19.1/debian/postrm	2020-05-29 11:57:44.000000000 +0000
@@ -0,0 +1,17 @@
+#!/bin/sh
+
+set -e
+
+if [ "$1" = 'upgrade' -a -n "$2" ]; then
+	# remove keys from the trusted.gpg file as they are now shipped in fragment files in trusted.gpg.d
+	if dpkg --compare-versions "$2" 'gt' "2016.09.19" && which gpg > /dev/null && which apt-key > /dev/null; then
+		TRUSTEDFILE='/etc/apt/trusted.gpg'
+		eval $(apt-config shell TRUSTEDFILE Apt::GPGV::TrustedKeyring)
+		eval $(apt-config shell TRUSTEDFILE Dir::Etc::Trusted/f)
+		if [ -e "$TRUSTEDFILE" ]; then
+			for KEY in 871920D1991BC93C; do
+				apt-key --keyring "$TRUSTEDFILE" del $KEY > /dev/null 2>&1 || :
+			done
+		fi
+	fi
+fi
diff -Nru ubuntu-keyring-2012.05.19/debian/rules ubuntu-keyring-2012.05.19.1/debian/rules
--- ubuntu-keyring-2012.05.19/debian/rules	2010-05-27 16:53:12.000000000 +0000
+++ ubuntu-keyring-2012.05.19.1/debian/rules	2020-05-29 11:58:19.000000000 +0000
@@ -28,6 +28,7 @@
 	-rm -rf debian/tmp
 	$(install_dir) debian/tmp/DEBIAN/
 	$(install_script) debian/postinst debian/tmp/DEBIAN/
+	$(install_script) debian/postrm debian/tmp/DEBIAN/
 
 	$(install_dir) debian/tmp/usr/share/keyrings/
 	$(install_file) keyrings/ubuntu-archive-keyring.gpg debian/tmp/usr/share/keyrings/
Binary files /tmp/tmp6iNv8u/KEyf071NwL/ubuntu-keyring-2012.05.19/keyrings/ubuntu-archive-keyring.gpg and /tmp/tmp6iNv8u/bbiBzQhJNr/ubuntu-keyring-2012.05.19.1/keyrings/ubuntu-archive-keyring.gpg differ
diff -Nru ubuntu-keyring-2012.05.19/md5sums.txt ubuntu-keyring-2012.05.19.1/md5sums.txt
--- ubuntu-keyring-2012.05.19/md5sums.txt	2012-05-19 01:30:17.000000000 +0000
+++ ubuntu-keyring-2012.05.19.1/md5sums.txt	2020-05-29 11:43:15.000000000 +0000
@@ -1,22 +1,20 @@
 -----BEGIN PGP SIGNED MESSAGE-----
-Hash: SHA256
+Hash: SHA512
 
-274895dfe6dd331fa1ae109c14745907  keyrings/ubuntu-archive-keyring.gpg
+331efe9b20032f3a8a73f291749deb68  keyrings/ubuntu-archive-keyring.gpg
 -----BEGIN PGP SIGNATURE-----
-Version: GnuPG v1.4.11 (GNU/Linux)
-Comment: Colin Watson <cjwatson@debian.org> -- Debian developer
 
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 -----END PGP SIGNATURE-----
diff -Nru ubuntu-keyring-2012.05.19/sha512sums.txt ubuntu-keyring-2012.05.19.1/sha512sums.txt
--- ubuntu-keyring-2012.05.19/sha512sums.txt	1970-01-01 00:00:00.000000000 +0000
+++ ubuntu-keyring-2012.05.19.1/sha512sums.txt	2020-05-29 11:44:22.000000000 +0000
@@ -0,0 +1,20 @@
+-----BEGIN PGP SIGNED MESSAGE-----
+Hash: SHA512
+
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+-----BEGIN PGP SIGNATURE-----
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