Enabled ETNB0 but cannot see it in ifconfig

Hi.

I'm experimenting with the Ethernet interfaces on connectors on the Renesas S4 Starter Kit (running Yocto as instructed here https://elinux.org/R-Car/Boards/S4SK/Yocto-Linux/SDK-v3.16.2) and would like to understand how to enable the ETNB0 (AVB 100Mbps). I have successfully been able to use TSN0 and TSN1 and would like to also use ETNB0, but I cannot find it.

I understand that ETNB0 needs to be enabled by using the Renesas S4 Starter Kit Configuration Tool and clicking the box 'ETNB0 enable', then click 'Write FGGA (non-volatile)' to save the settings. I have followed these steps, but I still only see TSN0, TSN1 and TSN2 in ifconfig.

Is there anything else I need to do to enable ETNB0?i

Also, can I confirm that TSN2 is not ETNB0?

Thank you in advance.