Putting 3BB homefiber router in bridge mode.

I have a question.

I have the 3BB Homefiber router. (AN5506-04-DG i belive)

I would like to put the 3BB router in bridge mode (to handle the FO-Ethernet conversion) and connect a Ubiquitu Security gateway router to handle the 3BB authentication and become my DHCP router.

My other network stuff (Switch and wireless AP) is also from Ubiquiti.

I know that i need to get the login and password from 3BB but do they allow me to place the 3BB provided router in bridge mode?

I hear conflicting stories and i don't want to mess around in the router before i know if it is possible.

I'm really interested in other people's experience with this.