Last update causing errors

I have had to deactivate your plugin following the update today due to it causing the website to throw out multiple error messages on both the front end and back end. Your support ticket page states there is no one in your office so I hope you see this and help before we have to move our clients to another support solution.

WP 4.9.8

Thanks.

example:

Warning: Cannot modify header information – headers already sent by (output started at /var/sites/s/**/public_html/wp-includes/cron.php:439) in /var/sites/s/**/public_html/wp-admin/includes/misc.php on line 1126

Document #1 is not an array in /var/sites/s/support.mediagorilla.uk/public_html/wp-includes/cron.php on line 439