When running borrowers-force-messaging-defaults.pl the error message 

DBD::mysql::st execute failed: Incorrect DATE value: '0000-00-00' [for Statement "SELECT DISTINCT bo.borrowernumber, bo.categorycode FROM borrowers bo
LEFT JOIN borrower_message_preferences mp USING (borrowernumber)

is displayed. 

According to documentation this relates to MySql variable sql_mode and that the following behavior can occur if sql_mode contains NO_ZERO_IN_DATE and/or NO_ZERO_DATE. 

I can confirm this by executing 

set sql_mode='STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE'; 

SELECT * FROM borrowers WHERE borrowers.dateenrolled >= '0000-00-00'

The select query will result in "Incorrect DATE value: '0000-00-00'" 

If I instead write 

set sql_mode='ALLOW_INVALID_DATES';

SELECT * FROM borrowers WHERE borrowers.dateenrolled >= '0000-00-00'

the select query executes correctly and returns a collection of borrowers BUT borrowers-force-messaging-defaults.pl still produces the error. 

Things I've checked 

* restarting MySql service 
* restarting server 
* that  <strict_sql_modes>0</strict_sql_modes> in koha-conf.xml is set to 0
* that /etc/mysql/mysql.conf.d/mysqld.cnf contains sql_mode = "ALLOW_INVALID_DATES"

Is this a bug in Koha or is there some configuration that I'm missing?