Dear developer,

systemd v258 introduced an incompatible change that affects pbuilder's
APT resolver:

systemd-run's --expand-environment= switch, which was disabled by
default when combined with --scope, has been changed to be enabled by
default. This brings cmdline expansion of transient scopes on par with
services.

It was announced in v257:

systemd-run's switch --expand-environment= which currently is disabled
by default when combined with --scope, will be changed in a future
release to be enabled by default.

pbuilder-checkparams needs to be fixed by adding option
--expand-environment=false in the stanza building the systemd-run 
command (lines 401-405).

Regards,