Diff of the two buildlogs:

--
--- b1/build.log	2023-04-12 12:55:01.678656120 +0000
+++ b2/build.log	2023-04-12 12:58:09.342386338 +0000
@@ -1,6 +1,6 @@
 I: pbuilder: network access will be disabled during build
-I: Current time: Tue May 14 07:15:49 -12 2024
-I: pbuilder-time-stamp: 1715714149
+I: Current time: Thu Apr 13 02:55:05 +14 2023
+I: pbuilder-time-stamp: 1681304105
 I: Building the build Environment
 I: extracting base tarball [/var/cache/pbuilder/bookworm-reproducible-base.tgz]
 I: copying local configuration
@@ -16,7 +16,7 @@
 I: copying [./libcommons-el-java_1.0.orig.tar.gz]
 I: copying [./libcommons-el-java_1.0-10.debian.tar.xz]
 I: Extracting source
-gpgv: Signature made Tue Jan 26 03:42:32 2021 -12
+gpgv: Signature made Wed Jan 27 05:42:32 2021 +14
 gpgv:                using RSA key B8CE4DE21080DCF903E16C40F513C419E4B9D0AC
 gpgv:                issuer "ebourg@apache.org"
 gpgv: Can't check signature: No public key
@@ -30,11 +30,20 @@
 dpkg-source: info: applying 0004-add-OSGi-metadata.patch
 I: using fakeroot in build.
 I: Installing the build-deps
-I: user script /srv/workspace/pbuilder/24441/tmp/hooks/D02_print_environment starting
+I: user script /srv/workspace/pbuilder/8367/tmp/hooks/D01_modify_environment starting
+debug: Running on codethink16-arm64.
+I: Changing host+domainname to test build reproducibility
+I: Adding a custom variable just for the fun of it...
+I: Changing /bin/sh to bash
+lrwxrwxrwx 1 root root 4 Jan  6 03:20 /bin/sh -> dash
+I: Setting pbuilder2's login shell to /bin/bash
+I: Setting pbuilder2's GECOS to second user,second room,second work-phone,second home-phone,second other
+I: user script /srv/workspace/pbuilder/8367/tmp/hooks/D01_modify_environment finished
+I: user script /srv/workspace/pbuilder/8367/tmp/hooks/D02_print_environment starting
 I: set
   BUILDDIR='/build'
-  BUILDUSERGECOS='first user,first room,first work-phone,first home-phone,first other'
-  BUILDUSERNAME='pbuilder1'
+  BUILDUSERGECOS='second user,second room,second work-phone,second home-phone,second other'
+  BUILDUSERNAME='pbuilder2'
   BUILD_ARCH='arm64'
   DEBIAN_FRONTEND='noninteractive'
   DEB_BUILD_OPTIONS='buildinfo=+all reproducible=+all parallel=8'
@@ -44,38 +53,38 @@
   IFS=' 	
   '
   LANG='C'
-  LANGUAGE='en_US:en'
+  LANGUAGE='nl_BE:nl'
   LC_ALL='C'
   MAIL='/var/mail/root'
   OPTIND='1'
-  PATH='/usr/sbin:/usr/bin:/sbin:/bin:/usr/games'
+  PATH='/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/i/capture/the/path'
   PBCURRENTCOMMANDLINEOPERATION='build'
   PBUILDER_OPERATION='build'
   PBUILDER_PKGDATADIR='/usr/share/pbuilder'
   PBUILDER_PKGLIBDIR='/usr/lib/pbuilder'
   PBUILDER_SYSCONFDIR='/etc'
-  PPID='24441'
+  PPID='8367'
   PS1='# '
   PS2='> '
   PS4='+ '
   PWD='/'
   SHELL='/bin/bash'
   SHLVL='2'
-  SUDO_COMMAND='/usr/bin/timeout -k 18.1h 18h /usr/bin/ionice -c 3 /usr/bin/nice /usr/sbin/pbuilder --build --configfile /srv/reproducible-results/rbuild-debian/r-b-build.00ZOZ9pO/pbuilderrc_scS2 --distribution bookworm --hookdir /etc/pbuilder/first-build-hooks --debbuildopts -b --basetgz /var/cache/pbuilder/bookworm-reproducible-base.tgz --buildresult /srv/reproducible-results/rbuild-debian/r-b-build.00ZOZ9pO/b1 --logfile b1/build.log libcommons-el-java_1.0-10.dsc'
+  SUDO_COMMAND='/usr/bin/timeout -k 24.1h 24h /usr/bin/ionice -c 3 /usr/bin/nice -n 11 /usr/bin/unshare --uts -- /usr/sbin/pbuilder --build --configfile /srv/reproducible-results/rbuild-debian/r-b-build.00ZOZ9pO/pbuilderrc_dWaO --distribution bookworm --hookdir /etc/pbuilder/rebuild-hooks --debbuildopts -b --basetgz /var/cache/pbuilder/bookworm-reproducible-base.tgz --buildresult /srv/reproducible-results/rbuild-debian/r-b-build.00ZOZ9pO/b2 --logfile b2/build.log --extrapackages usrmerge libcommons-el-java_1.0-10.dsc'
   SUDO_GID='117'
   SUDO_UID='110'
   SUDO_USER='jenkins'
   TERM='unknown'
-  TZ='/usr/share/zoneinfo/Etc/GMT+12'
+  TZ='/usr/share/zoneinfo/Etc/GMT-14'
   USER='root'
   USERNAME='root'
   _='/usr/bin/systemd-run'
   http_proxy='http://192.168.101.16:3128'
 I: uname -a
-  Linux codethink11-arm64 4.15.0-208-generic #220-Ubuntu SMP Mon Mar 20 14:28:12 UTC 2023 aarch64 GNU/Linux
+  Linux i-capture-the-hostname 4.15.0-208-generic #220-Ubuntu SMP Mon Mar 20 14:28:12 UTC 2023 aarch64 GNU/Linux
 I: ls -l /bin
-  lrwxrwxrwx 1 root root 7 May 12 04:50 /bin -> usr/bin
-I: user script /srv/workspace/pbuilder/24441/tmp/hooks/D02_print_environment finished
+  lrwxrwxrwx 1 root root 7 Apr 12 00:26 /bin -> usr/bin
+I: user script /srv/workspace/pbuilder/8367/tmp/hooks/D02_print_environment finished
  -> Attempting to satisfy build-dependencies
  -> Creating pbuilder-satisfydepends-dummy package
 Package: pbuilder-satisfydepends-dummy
@@ -263,7 +272,7 @@
 Get: 138 http://deb.debian.org/debian bookworm/main arm64 libjsp-api-java all 2.3.4-3 [53.7 kB]
 Get: 139 http://deb.debian.org/debian bookworm/main arm64 libservlet-api-java all 4.0.1-2 [81.0 kB]
 Get: 140 http://deb.debian.org/debian bookworm/main arm64 maven-repo-helper all 1.11 [142 kB]
-Fetched 348 MB in 1min 1s (5747 kB/s)
+Fetched 348 MB in 54s (6465 kB/s)
 debconf: delaying package configuration, since apt-utils is not installed
 Selecting previously unselected package sensible-utils.
 (Reading database ... 
(Reading database ... 5%
(Reading database ... 10%
(Reading database ... 15%
(Reading database ... 20%
(Reading database ... 25%
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(Reading database ... 35%
(Reading database ... 40%
(Reading database ... 45%
(Reading database ... 50%
(Reading database ... 55%
(Reading database ... 60%
(Reading database ... 65%
(Reading database ... 70%
(Reading database ... 75%
(Reading database ... 80%
(Reading database ... 85%
(Reading database ... 90%
(Reading database ... 95%
(Reading database ... 100%
(Reading database ... 19616 files and directories currently installed.)
@@ -1024,10 +1033,15 @@
 Reading package lists...
 Building dependency tree...
 Reading state information...
+usrmerge is already the newest version (35).
 fakeroot is already the newest version (1.31-1.2).
 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
 I: Building the package
-I: Running cd /build/libcommons-el-java-1.0/ && env PATH="/usr/sbin:/usr/bin:/sbin:/bin:/usr/games" HOME="/nonexistent/first-build" dpkg-buildpackage -us -uc -b && env PATH="/usr/sbin:/usr/bin:/sbin:/bin:/usr/games" HOME="/nonexistent/first-build" dpkg-genchanges -S  > ../libcommons-el-java_1.0-10_source.changes
+I: user script /srv/workspace/pbuilder/8367/tmp/hooks/A99_set_merged_usr starting
+Re-configuring usrmerge...
+I: user script /srv/workspace/pbuilder/8367/tmp/hooks/A99_set_merged_usr finished
+hostname: Temporary failure in name resolution
+I: Running cd /build/libcommons-el-java-1.0/ && env PATH="/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/i/capture/the/path" HOME="/nonexistent/second-build" dpkg-buildpackage -us -uc -b && env PATH="/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/i/capture/the/path" HOME="/nonexistent/second-build" dpkg-genchanges -S  > ../libcommons-el-java_1.0-10_source.changes
 dpkg-buildpackage: info: source package libcommons-el-java
 dpkg-buildpackage: info: source version 1.0-10
 dpkg-buildpackage: info: source distribution unstable
@@ -1043,7 +1057,7 @@
 clean:
 
 BUILD SUCCESSFUL
-Total time: 1 second
+Total time: 2 seconds
    dh_clean
  debian/rules build
 dh build --with maven-repo-helper
@@ -1142,7 +1156,7 @@
       [jar] Building jar: /build/libcommons-el-java-1.0/dist/commons-el.jar
 
 BUILD SUCCESSFUL
-Total time: 7 seconds
+Total time: 21 seconds
 make[1]: Leaving directory '/build/libcommons-el-java-1.0'
    dh_auto_test
    create-stamp debian/debhelper-build-stamp
@@ -1173,12 +1187,14 @@
 dpkg-buildpackage: info: binary-only upload (no source included)
 dpkg-genchanges: info: not including original source code in upload
 I: copying local configuration
+I: user script /srv/workspace/pbuilder/8367/tmp/hooks/B01_cleanup starting
+I: user script /srv/workspace/pbuilder/8367/tmp/hooks/B01_cleanup finished
 I: unmounting dev/ptmx filesystem
 I: unmounting dev/pts filesystem
 I: unmounting dev/shm filesystem
 I: unmounting proc filesystem
 I: unmounting sys filesystem
 I: cleaning the build env 
-I: removing directory /srv/workspace/pbuilder/24441 and its subdirectories
-I: Current time: Tue May 14 07:18:00 -12 2024
-I: pbuilder-time-stamp: 1715714280
+I: removing directory /srv/workspace/pbuilder/8367 and its subdirectories
+I: Current time: Thu Apr 13 02:58:08 +14 2023
+I: pbuilder-time-stamp: 1681304288