[27-Sep-2017 21:35:26 UTC] PHP Notice: Undefined index: tab in /var/www/mysite.com/wp-content/plugins/vcaching/vcaching.php on line 567
[27-Sep-2017 21:35:26 UTC] PHP Notice: Undefined index: tab in /var/www/mysite.com/wp-content/plugins/vcaching/vcaching.php on line 569
[27-Sep-2017 21:35:26 UTC] PHP Notice: Undefined index: tab in /var/www/mysite.com/wp-content/plugins/vcaching/vcaching.php on line 571
[27-Sep-2017 21:36:02 UTC] PHP Notice: Undefined index: tab in /var/www/mysite.com/wp-content/plugins/vcaching/vcaching.php on line 567
[27-Sep-2017 21:36:02 UTC] PHP Notice: Undefined index: tab in /var/www/mysite.com/wp-content/plugins/vcaching/vcaching.php on line 569
[27-Sep-2017 21:36:02 UTC] PHP Notice: Undefined index: tab in /var/www/mysite.com/wp-content/plugins/vcaching/vcaching.php on line 571
Debug log is full of these messages: