The response given by a mail means nothing. One cant tell if you are stuck or not. Some visa offices like sydney are slower than others. Sometimes additional verification is required like contacting employees etc. Sometimes you reach IP2 so quick and your security screening takes time. Its just all speculations by us and my best advise is not to contact them anymore. Wait as long as your are within the time frame of 6 months. Meanwhile, like i said if you reach 60 days post AOR without changes and you are worried, order gcms notes, its the only way you can tell for real whats going on with your file.