AU Internet – Can you use your own router?

Hi guys, I got AU's BL3000HM router but am interested in getting my own router (I'm thinking of the Ubiquiti Fiber Gateway with an AP in a more central part of my house).

I asked AU if I can set up my own device without their router in between but all I got was "I'm not sure, try it and see". Have any of you set up your own equipment without the AU router?