Upgrade to Anspress 4

Upgraded one live site and got:

[11-Feb-2017 16:41:59 UTC] WordPress database error You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near ‘post_type IN (‘question’, ‘answer’) LIMIT 0,50′ at line 1 for query SELECT SQL_CALC_FOUND_ROWS ID, post_type, post_parent, post_status FROM wp_posts LEFT JOIN wp_ap_qameta ON post_id = ID WHERE ptype IS NULL post_type IN (‘question’, ‘answer’) LIMIT 0,50 made by do_action(‘wp_ajax_ap_migrator_4x’), WP_Hook->do_action, WP_Hook->apply_filters, AnsPress_Admin_Ajax::ap_migrator_4x, AP_Update_Helper->__construct, AP_Update_Helper->migrate_post_data