You could always book the appointment now with the Monash IVF doctor for a future date of your choice and worry about getting the referral when it gets closer (you only need to have the referral prior to/day of the appointment). What I would do is also book your appointment with the GP the week prior to the FS appointment - then you know you can get the referral prior to the appointment. If you don't end up needing the consult - great - just cancel the appointments.