auto block posts with premium category

add_filter( 'jeg_metabox', 'j_override_paywall_block', 99, 2 );

function j_override_paywall_block( $default, $name ) {
    if ( 'jnews_paywall_metabox.enable_premium_post' === $name ) {
        if ( has_category( 'premium-post' ) ) { /* change premium-post with your Premium Post category slug */
            return true;
        }
    }
    return $default;
}