pjiang老师，填表问题请教

在这个帖子里 http://blog.wenxuecity.com/blogview.php?date=200709&postID=27583&page=1#mark pjiang老师，请问如果是successor in interest company file h1b extension. Part 2. Information about this petition. 应该算b. Continuation of previously approved employment without change with the same employer 延期 还是c. Change in previously approved employment. 雇佣改变 谢谢！