Diff of the two buildlogs:

--
--- b1/build.log	2020-04-24 01:48:32.202417928 +0000
+++ b2/build.log	2020-04-24 01:48:48.370098129 +0000
@@ -1,6 +1,6 @@
 I: pbuilder: network access will be disabled during build
-I: Current time: Thu Apr 23 13:44:57 -12 2020
-I: pbuilder-time-stamp: 1587692697
+I: Current time: Thu May 27 22:11:32 +14 2021
+I: pbuilder-time-stamp: 1622103092
 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 Mon Jul 14 19:32:07 2008 -12
+gpgv: Signature made Tue Jul 15 21:32:07 2008 +14
 gpgv:                using DSA key 189A3241BC70A6FF
 gpgv: Can't check signature: No public key
 dpkg-source: warning: failed to verify signature on ./tinydyndns_0.4.2.debian1-1.dsc
@@ -27,6 +27,18 @@
 dpkg-source: info: applying tinydyndns_0.4.2.debian1-1.diff.gz
 I: using fakeroot in build.
 I: Installing the build-deps
+I: user script /srv/workspace/pbuilder/55126/tmp/hooks/D01_modify_environment starting
+debug: Running on profitbricks-build6-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/55126/tmp/hooks/D01_modify_environment finished
  -> Attempting to satisfy build-dependencies
  -> Creating pbuilder-satisfydepends-dummy package
 Package: pbuilder-satisfydepends-dummy
@@ -68,7 +80,7 @@
 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/tinydyndns-0.4.2.debian1/ && env PATH="/usr/sbin:/usr/bin:/sbin:/bin:/usr/games" HOME="/nonexistent/first-build" dpkg-buildpackage -us -uc -b
+I: Running cd /build/tinydyndns-0.4.2.debian1/ && 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 tinydyndns
 dpkg-buildpackage: info: source version 0.4.2.debian1-1
 dpkg-buildpackage: info: source distribution unstable
@@ -328,12 +340,14 @@
  dpkg-source --after-build .
 dpkg-buildpackage: info: binary-only upload (no source included)
 I: copying local configuration
+I: user script /srv/workspace/pbuilder/55126/tmp/hooks/B01_cleanup starting
+I: user script /srv/workspace/pbuilder/55126/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/22409 and its subdirectories
-I: Current time: Thu Apr 23 13:48:31 -12 2020
-I: pbuilder-time-stamp: 1587692911
+I: removing directory /srv/workspace/pbuilder/55126 and its subdirectories
+I: Current time: Thu May 27 22:11:46 +14 2021
+I: pbuilder-time-stamp: 1622103106