Hi Meg I received the same letter in December and my medical had expired so I quickly went and got it done again. Since then no reply or status update.
May I ask what is your status on the application? Is it still "Received" like mine?
Also was there a person's name and position number at the end of the letter? Mine has and I thought its my Case officer but unsure.
I received the email from qld.pp.processing@homeaffrairs is yours the same too? :)