Hi Samuel,
I removed pre-squeeze upgrade code
Regarding your change 'Bump DH level to 12' I believe debian/control
needs further changes.
The debhelper manpage says:
Changes from v11 are:
[...]
This change makes dh_installinit inject a misc:Pre-Depends
for init-system-helpers (>= 1.54~). Please ensure that the
package lists ${misc:Pre-Depends} in its Pre-Depends field
before upgrading to compat 12.
[...]
Please double-check.
Best,
Sven