League Table: Edit mode Exceptions

Hello,

Getting the following exceptions when trying to edit League table. SportsPress v 2.5.3. Edit page won’t load beyond displaying points for the first team in the table and right-hand side is not renders properly either.

[[26-Nov-2017 20:26:03 Europe/Stockholm] PHP Fatal error: Uncaught Error: Call to undefined function readonly() in [path]/wp-content/plugins/sportspress/includes/admin/post-types/meta-boxes/class-sp-meta-box-table-data.php:125
Stack trace:
#0 [path]/wp-content/plugins/sportspress/includes/admin/post-types/meta-boxes/class-sp-meta-box-table-data.php(26): SP_Meta_Box_Table_Data::table(717, Array, Array, Array, Array, Array, ‘0’)
#1 [path]/wp-admin/includes/template.php(1048): SP_Meta_Box_Table_Data::output(Object(WP_Post), Array)
#2 [path]/wp-admin/edit-form-advanced.php(703): do_meta_boxes(Object(WP_Screen), ‘normal’, Object(WP_Post))
#3 [path]/wp-admin/post.php(173): include(‘[path1]/…’)
#4 {main}
thrown in [path]/wp-content/plugins/sportspress/includes/admin/post-types/meta-boxes/class-sp-meta-box-table-data.php on line 125