Now that I've had both my Pfizer shots I'm able to access the online booking system again and check availability. So with regard to the 'people in Melbourne can't get an appointment within 6 weeks of their first Pfizer' statement, this is what I see today if I look for availability.
Showgrounds....676 appointments between now and 28/07...so essentially any day between now and then and abundance of options.
View attachment 251763Convention Centre...370 options....pick a time tomorrow
View attachment 251764Sandown - 239 options
View attachment 251765
...and of course there are many more options to choose from.
I strongly would think that these complaints are arising from people not being able to book into the venue of their choosing. For example, the Alfred where I went is much smaller and has no availability.