diff -U3 /tmp/cirrus-ci-build/src/test/regress/expected/timestamptz.out /tmp/cirrus-ci-build/src/bin/pg_upgrade/tmp_check/results/timestamptz.out
--- /tmp/cirrus-ci-build/src/test/regress/expected/timestamptz.out	2024-12-24 05:44:09.801446819 +0000
+++ /tmp/cirrus-ci-build/src/bin/pg_upgrade/tmp_check/results/timestamptz.out	2024-12-24 05:47:49.905456024 +0000
@@ -184,30 +184,22 @@
 (1 row)
 
 SELECT 'Jan 01 00:00:00 1000 LMT'::timestamptz;
-         timestamptz          
-------------------------------
- Wed Jan 01 00:00:00 1000 LMT
-(1 row)
-
+ERROR:  invalid input syntax for type timestamp with time zone: "Jan 01 00:00:00 1000 LMT"
+LINE 1: SELECT 'Jan 01 00:00:00 1000 LMT'::timestamptz;
+               ^
 SELECT 'Jan 01 00:00:00 2024 LMT'::timestamptz;
-         timestamptz          
-------------------------------
- Sun Dec 31 23:52:58 2023 PST
-(1 row)
-
+ERROR:  invalid input syntax for type timestamp with time zone: "Jan 01 00:00:00 2024 LMT"
+LINE 1: SELECT 'Jan 01 00:00:00 2024 LMT'::timestamptz;
+               ^
 SET timezone = 'Europe/London';
 SELECT 'Jan 01 00:00:00 1000 LMT'::timestamptz;
-         timestamptz          
-------------------------------
- Wed Jan 01 00:00:00 1000 LMT
-(1 row)
-
+ERROR:  invalid input syntax for type timestamp with time zone: "Jan 01 00:00:00 1000 LMT"
+LINE 1: SELECT 'Jan 01 00:00:00 1000 LMT'::timestamptz;
+               ^
 SELECT 'Jan 01 00:00:00 2024 LMT'::timestamptz;
-         timestamptz          
-------------------------------
- Mon Jan 01 00:01:15 2024 GMT
-(1 row)
-
+ERROR:  invalid input syntax for type timestamp with time zone: "Jan 01 00:00:00 2024 LMT"
+LINE 1: SELECT 'Jan 01 00:00:00 2024 LMT'::timestamptz;
+               ^
 -- which might be nothing
 SET timezone = 'UTC';
 SELECT 'Jan 01 00:00:00 2024 LMT'::timestamptz;  -- fail
diff -U3 /tmp/cirrus-ci-build/src/test/regress/expected/horology.out /tmp/cirrus-ci-build/src/bin/pg_upgrade/tmp_check/results/horology.out
--- /tmp/cirrus-ci-build/src/test/regress/expected/horology.out	2024-12-24 05:44:09.741656604 +0000
+++ /tmp/cirrus-ci-build/src/bin/pg_upgrade/tmp_check/results/horology.out	2024-12-24 05:47:52.209461456 +0000
@@ -3333,11 +3333,8 @@
 (1 row)
 
 SELECT to_timestamp('2011-12-18 00:00 LMT', 'YYYY-MM-DD HH24:MI TZ');  -- dyntz
-         to_timestamp         
-------------------------------
- Sat Dec 17 23:52:58 2011 PST
-(1 row)
-
+ERROR:  invalid value "LMT" for "TZ"
+DETAIL:  Time zone abbreviation is not recognized.
 SELECT to_timestamp('2011-12-18 11:38ESTFOO24', 'YYYY-MM-DD HH12:MITZFOOSS');
          to_timestamp         
 ------------------------------