Diff of the two buildlogs:

--
--- b1/build.log	2020-05-02 12:50:42.924176971 +0000
+++ b2/build.log	2020-05-02 12:51:07.451692057 +0000
@@ -1,6 +1,6 @@
 I: pbuilder: network access will be disabled during build
-I: Current time: Sat May  2 00:43:51 -12 2020
-I: pbuilder-time-stamp: 1588423431
+I: Current time: Sat Jun  5 09:13:44 +14 2021
+I: pbuilder-time-stamp: 1622834024
 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 Sun Dec 25 09:41:25 2016 -12
+gpgv: Signature made Mon Dec 26 11:41:25 2016 +14
 gpgv:                using RSA key B3F51A2712619C3ECD74B8E178494EF72375A66C
 gpgv: Can't check signature: No public key
 dpkg-source: warning: failed to verify signature on ./spkproxy_1.4.8-4.4.dsc
@@ -34,6 +34,18 @@
  spkproxy-1.4.8/spkproxy.py
 I: using fakeroot in build.
 I: Installing the build-deps
+I: user script /srv/workspace/pbuilder/43074/tmp/hooks/D01_modify_environment starting
+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/43074/tmp/hooks/D01_modify_environment finished
  -> Attempting to satisfy build-dependencies
  -> Creating pbuilder-satisfydepends-dummy package
 Package: pbuilder-satisfydepends-dummy
@@ -132,7 +144,7 @@
 Get: 57 http://deb.debian.org/debian buster/main i386 python3-lib2to3 all 3.7.3-1 [76.7 kB]
 Get: 58 http://deb.debian.org/debian buster/main i386 python3-distutils all 3.7.3-1 [142 kB]
 Get: 59 http://deb.debian.org/debian buster/main i386 dh-python all 3.20190308 [99.3 kB]
-Fetched 30.4 MB in 9s (3262 kB/s)
+Fetched 30.4 MB in 0s (82.9 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.)
@@ -395,7 +407,7 @@
 fakeroot is already the newest version (1.23-1).
 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
 I: Building the package
-I: Running cd /build/spkproxy-1.4.8/ && env PATH="/usr/sbin:/usr/bin:/sbin:/bin:/usr/games" HOME="/nonexistent/first-build" dpkg-buildpackage -us -uc -b
+I: Running cd /build/spkproxy-1.4.8/ && 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 spkproxy
 dpkg-buildpackage: info: source version 1.4.8-4.4
 dpkg-buildpackage: info: source distribution unstable
@@ -475,12 +487,14 @@
  dpkg-source --after-build .
 dpkg-buildpackage: info: binary-only upload (no source included)
 I: copying local configuration
+I: user script /srv/workspace/pbuilder/43074/tmp/hooks/B01_cleanup starting
+I: user script /srv/workspace/pbuilder/43074/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/16653 and its subdirectories
-I: Current time: Sat May  2 00:50:42 -12 2020
-I: pbuilder-time-stamp: 1588423842
+I: removing directory /srv/workspace/pbuilder/43074 and its subdirectories
+I: Current time: Sat Jun  5 09:14:07 +14 2021
+I: pbuilder-time-stamp: 1622834047