bbPress.org

Hmm… easy way of doing that

function bb_reset_newpostlink() {

global $link, $topic_id;

$link = get_topic_link( $topic_id );

}

add_action( 'bb-post.php', 'bb_reset_newpostlink' );

Put that in either functions.php or a plugin, it’ll overwrite the redirect link with the general topic one.