Diff of the two buildlogs:

--
--- b1/build.log	2020-04-12 06:05:44.543616042 +0000
+++ b2/build.log	2020-04-12 06:06:02.971259059 +0000
@@ -1,6 +1,6 @@
 I: pbuilder: network access will be disabled during build
-I: Current time: Sat Apr 11 18:02:44 -12 2020
-I: pbuilder-time-stamp: 1586671364
+I: Current time: Sun May 16 02:28:45 +14 2021
+I: pbuilder-time-stamp: 1621081725
 I: Building the build Environment
 I: extracting base tarball [/var/cache/pbuilder/buster-reproducible-base.tgz]
 I: copying local configuration
@@ -18,7 +18,7 @@
 I: Extracting source
 gpgv: unknown type of key resource 'trustedkeys.kbx'
 gpgv: keyblock resource '/root/.gnupg/trustedkeys.kbx': General error
-gpgv: Signature made Sat Dec  1 21:37:11 2018 -12
+gpgv: Signature made Sun Dec  2 23:37:11 2018 +14
 gpgv:                using RSA key F1FF5D0D7E002DF0FE55FB0CA65B78DBE67C7AAC
 gpgv: Can't check signature: No public key
 dpkg-source: warning: failed to verify signature on ./sparkline-php_0.2-7.dsc
@@ -27,6 +27,18 @@
 dpkg-source: info: unpacking sparkline-php_0.2-7.debian.tar.xz
 I: Not using root during the build.
 I: Installing the build-deps
+I: user script /srv/workspace/pbuilder/42603/tmp/hooks/D01_modify_environment starting
+disorder-fs debug: Running on profitbricks-build16-i386.
+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
+Removing 'diversion of /bin/sh to /bin/sh.distrib by dash'
+Adding 'diversion of /bin/sh to /bin/sh.distrib by bash'
+Removing 'diversion of /usr/share/man/man1/sh.1.gz to /usr/share/man/man1/sh.distrib.1.gz by dash'
+Adding 'diversion of /usr/share/man/man1/sh.1.gz to /usr/share/man/man1/sh.distrib.1.gz by 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/42603/tmp/hooks/D01_modify_environment finished
  -> Attempting to satisfy build-dependencies
  -> Creating pbuilder-satisfydepends-dummy package
 Package: pbuilder-satisfydepends-dummy
@@ -95,7 +107,7 @@
 Get: 31 http://deb.debian.org/debian buster/main i386 intltool-debian all 0.35.0+20060710.5 [26.8 kB]
 Get: 32 http://deb.debian.org/debian buster/main i386 po-debconf all 1.0.21 [248 kB]
 Get: 33 http://deb.debian.org/debian buster/main i386 debhelper all 12.1.1 [1016 kB]
-Fetched 19.4 MB in 5s (4185 kB/s)
+Fetched 19.4 MB in 0s (81.3 MB/s)
 debconf: delaying package configuration, since apt-utils is not installed
 Selecting previously unselected package libbsd0:i386.
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(Reading database ... 19231 files and directories currently installed.)
@@ -245,7 +257,7 @@
 Building tag database...
  -> Finished parsing the build-deps
 I: Building the package
-I: Running cd /build/sparkline-php-0.2/ && env PATH="/usr/sbin:/usr/bin:/sbin:/bin:/usr/games" HOME="/nonexistent/first-build" dpkg-buildpackage -us -uc -b
+I: Running cd /build/sparkline-php-0.2/ && env PATH="/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/i/capture/the/path" HOME="/nonexistent/second-build" dpkg-buildpackage -us -uc -b
 dpkg-buildpackage: info: source package sparkline-php
 dpkg-buildpackage: info: source version 0.2-7
 dpkg-buildpackage: info: source distribution unstable
@@ -283,12 +295,14 @@
  dpkg-source --after-build .
 dpkg-buildpackage: info: binary-only upload (no source included)
 I: copying local configuration
+I: user script /srv/workspace/pbuilder/42603/tmp/hooks/B01_cleanup starting
+I: user script /srv/workspace/pbuilder/42603/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/29710 and its subdirectories
-I: Current time: Sat Apr 11 18:05:44 -12 2020
-I: pbuilder-time-stamp: 1586671544
+I: removing directory /srv/workspace/pbuilder/42603 and its subdirectories
+I: Current time: Sun May 16 02:29:00 +14 2021
+I: pbuilder-time-stamp: 1621081740