What is the fastest way for me to apply a hksar passport and how long will it take?

Hi everyone, i am hong kong citizen and holding hk id with BNO passport. I am currently holging permanent resisdent in sydney. I would like to back hong kong for travel around 10 days, i realise that my BNO has been expired for 6 months already. What is the fastest way for me to apply a hksar passport and how long will it take? Thank you