Just noticed while working on something else. When adding a patron to a routing list, there are several warns in the logs: Use of uninitialized value in numeric gt (>) at /home/vagrant/kohaclone/C4/Serials.pm line 1973. Use of uninitialized value in concatenation (.) or string at /home/vagrant/kohaclone/serials/routing-preview.pl line 126.
Some more on saving the routing list: Use of uninitialized value in numeric eq (==) at /home/vagrant/kohaclone/serials/routing-preview.pl line 89. Use of uninitialized value in concatenation (.) or string at /home/vagrant/kohaclone/serials/routing-preview.pl line 126.