Diff of the two buildlogs:

--
--- b1/build.log	2024-01-07 17:39:40.201925294 +0000
+++ b2/build.log	2024-01-07 17:41:20.993894188 +0000
@@ -1,6 +1,6 @@
 I: pbuilder: network access will be disabled during build
-I: Current time: Sun Jan  7 05:37:14 -12 2024
-I: pbuilder-time-stamp: 1704649034
+I: Current time: Mon Jan  8 07:39:53 +14 2024
+I: pbuilder-time-stamp: 1704649193
 I: Building the build Environment
 I: extracting base tarball [/var/cache/pbuilder/bookworm-reproducible-base.tgz]
 I: copying local configuration
@@ -25,49 +25,81 @@
 dpkg-source: info: unpacking cpanoutdated_0.32-2.debian.tar.xz
 I: using fakeroot in build.
 I: Installing the build-deps
-I: user script /srv/workspace/pbuilder/31863/tmp/hooks/D02_print_environment starting
+I: user script /srv/workspace/pbuilder/26332/tmp/hooks/D01_modify_environment starting
+debug: Running on virt64b.
+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
+'/bin/sh' -> '/bin/bash'
+lrwxrwxrwx 1 root root 9 Jan  7 17:40 /bin/sh -> /bin/bash
+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/26332/tmp/hooks/D01_modify_environment finished
+I: user script /srv/workspace/pbuilder/26332/tmp/hooks/D02_print_environment starting
 I: set
-  BUILDDIR='/build/reproducible-path'
-  BUILDUSERGECOS='first user,first room,first work-phone,first home-phone,first other'
-  BUILDUSERNAME='pbuilder1'
-  BUILD_ARCH='armhf'
-  DEBIAN_FRONTEND='noninteractive'
-  DEB_BUILD_OPTIONS='buildinfo=+all reproducible=+all parallel=3 '
-  DISTRIBUTION='bookworm'
-  HOME='/root'
-  HOST_ARCH='armhf'
+  BASH=/bin/sh
+  BASHOPTS=checkwinsize:cmdhist:complete_fullquote:extquote:force_fignore:globasciiranges:globskipdots:hostcomplete:interactive_comments:patsub_replacement:progcomp:promptvars:sourcepath
+  BASH_ALIASES=()
+  BASH_ARGC=()
+  BASH_ARGV=()
+  BASH_CMDS=()
+  BASH_LINENO=([0]="12" [1]="0")
+  BASH_LOADABLES_PATH=/usr/local/lib/bash:/usr/lib/bash:/opt/local/lib/bash:/usr/pkg/lib/bash:/opt/pkg/lib/bash:.
+  BASH_SOURCE=([0]="/tmp/hooks/D02_print_environment" [1]="/tmp/hooks/D02_print_environment")
+  BASH_VERSINFO=([0]="5" [1]="2" [2]="15" [3]="1" [4]="release" [5]="arm-unknown-linux-gnueabihf")
+  BASH_VERSION='5.2.15(1)-release'
+  BUILDDIR=/build/reproducible-path
+  BUILDUSERGECOS='second user,second room,second work-phone,second home-phone,second other'
+  BUILDUSERNAME=pbuilder2
+  BUILD_ARCH=armhf
+  DEBIAN_FRONTEND=noninteractive
+  DEB_BUILD_OPTIONS='buildinfo=+all reproducible=+all parallel=4 '
+  DIRSTACK=()
+  DISTRIBUTION=bookworm
+  EUID=0
+  FUNCNAME=([0]="Echo" [1]="main")
+  GROUPS=()
+  HOME=/root
+  HOSTNAME=i-capture-the-hostname
+  HOSTTYPE=arm
+  HOST_ARCH=armhf
   IFS=' 	
   '
-  INVOCATION_ID='3f0a980b5a7b47daabebc84fc645e203'
-  LANG='C'
-  LANGUAGE='en_US:en'
-  LC_ALL='C'
-  MAIL='/var/mail/root'
-  OPTIND='1'
-  PATH='/usr/sbin:/usr/bin:/sbin:/bin:/usr/games'
-  PBCURRENTCOMMANDLINEOPERATION='build'
-  PBUILDER_OPERATION='build'
-  PBUILDER_PKGDATADIR='/usr/share/pbuilder'
-  PBUILDER_PKGLIBDIR='/usr/lib/pbuilder'
-  PBUILDER_SYSCONFDIR='/etc'
-  PPID='31863'
-  PS1='# '
-  PS2='> '
+  INVOCATION_ID=bbb62c8a3d8e4b94ac5c7a6729f7e4dd
+  LANG=C
+  LANGUAGE=it_CH:it
+  LC_ALL=C
+  MACHTYPE=arm-unknown-linux-gnueabihf
+  MAIL=/var/mail/root
+  OPTERR=1
+  OPTIND=1
+  OSTYPE=linux-gnueabihf
+  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
+  PIPESTATUS=([0]="0")
+  POSIXLY_CORRECT=y
+  PPID=26332
   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.aQC5dghn/pbuilderrc_iT5y --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.aQC5dghn/b1 --logfile b1/build.log cpanoutdated_0.32-2.dsc'
-  SUDO_GID='113'
-  SUDO_UID='107'
-  SUDO_USER='jenkins'
-  TERM='unknown'
-  TZ='/usr/share/zoneinfo/Etc/GMT+12'
-  USER='root'
-  _='/usr/bin/systemd-run'
-  http_proxy='http://10.0.0.15:3142/'
+  PWD=/
+  SHELL=/bin/bash
+  SHELLOPTS=braceexpand:errexit:hashall:interactive-comments:posix
+  SHLVL=3
+  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.aQC5dghn/pbuilderrc_MZv1 --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.aQC5dghn/b2 --logfile b2/build.log cpanoutdated_0.32-2.dsc'
+  SUDO_GID=113
+  SUDO_UID=107
+  SUDO_USER=jenkins
+  TERM=unknown
+  TZ=/usr/share/zoneinfo/Etc/GMT-14
+  UID=0
+  USER=root
+  _='I: set'
+  http_proxy=http://10.0.0.15:3142/
 I: uname -a
-  Linux wbq0 6.1.0-17-armmp #1 SMP Debian 6.1.69-1 (2023-12-30) armv7l GNU/Linux
+  Linux i-capture-the-hostname 6.1.0-17-arm64 #1 SMP Debian 6.1.69-1 (2023-12-30) aarch64 GNU/Linux
 I: ls -l /bin
   total 4964
   -rwxr-xr-x 1 root root 838488 Apr 23  2023 bash
@@ -127,7 +159,7 @@
   -rwxr-xr-x 1 root root  67600 Sep 20  2022 rmdir
   -rwxr-xr-x 1 root root  14152 Jul 28 23:46 run-parts
   -rwxr-xr-x 1 root root 133372 Jan  5  2023 sed
-  lrwxrwxrwx 1 root root      4 Jan  5  2023 sh -> dash
+  lrwxrwxrwx 1 root root      9 Jan  7 17:40 sh -> /bin/bash
   -rwxr-xr-x 1 root root  67584 Sep 20  2022 sleep
   -rwxr-xr-x 1 root root  67644 Sep 20  2022 stty
   -rwsr-xr-x 1 root root  50800 Mar 23  2023 su
@@ -153,7 +185,7 @@
   -rwxr-xr-x 1 root root   2206 Apr 10  2022 zless
   -rwxr-xr-x 1 root root   1842 Apr 10  2022 zmore
   -rwxr-xr-x 1 root root   4577 Apr 10  2022 znew
-I: user script /srv/workspace/pbuilder/31863/tmp/hooks/D02_print_environment finished
+I: user script /srv/workspace/pbuilder/26332/tmp/hooks/D02_print_environment finished
  -> Attempting to satisfy build-dependencies
  -> Creating pbuilder-satisfydepends-dummy package
 Package: pbuilder-satisfydepends-dummy
@@ -262,7 +294,7 @@
 Get: 61 http://deb.debian.org/debian bookworm/main armhf libwww-perl all 6.68-1 [186 kB]
 Get: 62 http://deb.debian.org/debian bookworm/main armhf liblwp-protocol-https-perl all 6.10-1 [12.2 kB]
 Get: 63 http://deb.debian.org/debian bookworm/main armhf libmodule-build-tiny-perl all 0.039-2 [12.2 kB]
-Fetched 21.4 MB in 2s (11.1 MB/s)
+Fetched 21.4 MB in 3s (6399 kB/s)
 debconf: delaying package configuration, since apt-utils is not installed
 Selecting previously unselected package netbase.
 (Reading database ... 
(Reading database ... 5%
(Reading database ... 10%
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(Reading database ... 45%
(Reading database ... 50%
(Reading database ... 55%
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(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 ... 17881 files and directories currently installed.)
@@ -543,7 +575,11 @@
 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/reproducible-path/cpanoutdated-0.32/ && 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  > ../cpanoutdated_0.32-2_source.changes
+I: user script /srv/workspace/pbuilder/26332/tmp/hooks/A99_set_merged_usr starting
+Not re-configuring usrmerge for bookworm
+I: user script /srv/workspace/pbuilder/26332/tmp/hooks/A99_set_merged_usr finished
+hostname: Name or service not known
+I: Running cd /build/reproducible-path/cpanoutdated-0.32/ && 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  > ../cpanoutdated_0.32-2_source.changes
 dpkg-buildpackage: info: source package cpanoutdated
 dpkg-buildpackage: info: source version 0.32-2
 dpkg-buildpackage: info: source distribution unstable
@@ -590,7 +626,7 @@
 ok 6
 ok
 All tests successful.
-Files=3, Tests=14,  4 wallclock secs ( 0.16 usr  0.05 sys +  3.38 cusr  0.29 csys =  3.88 CPU)
+Files=3, Tests=14,  1 wallclock secs ( 0.06 usr  0.00 sys +  1.26 cusr  0.08 csys =  1.40 CPU)
 Result: PASS
    create-stamp debian/debhelper-build-stamp
  fakeroot debian/rules binary
@@ -624,12 +660,14 @@
 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/26332/tmp/hooks/B01_cleanup starting
+I: user script /srv/workspace/pbuilder/26332/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/31863 and its subdirectories
-I: Current time: Sun Jan  7 05:39:33 -12 2024
-I: pbuilder-time-stamp: 1704649173
+I: removing directory /srv/workspace/pbuilder/26332 and its subdirectories
+I: Current time: Mon Jan  8 07:41:15 +14 2024
+I: pbuilder-time-stamp: 1704649275