Unable to install Copter beta on a quad with APM Planner?

I would like to install the current 3.5 beta on my quad, but APM Planner only shows the stable release for Quad frame types. It shows the beta for traditional helicopters…but that seems to clearly be the wrong firmware.

I thought I would just download the firmware from http://firmware.us.ardupilot.org/Copter/beta/PX4/, but there are several files there and it wasn’t clear to me if I needed one or all of them.

So, it looks like the answer was ArduCopter-v2.px4, which I was able to install using the “custom” option. Still curious why APM Planner doesn’t show the beta firmware for anything other than helis.

The current master should show the beta files and should be able to configure it.