ISP Modem In Bridge Mode, advice?

Hi,

I have an RT-AC86U with WRT-Merlin 384.7_2

Skynet and Diversion are installed and running well. Also, the OpenVPN server is running, and I have a OpenVPN Client connected to a paid VPN service running.

And in AiProtection in the "Router Security Assessment" all the fields are green (i.e. UPnP is disabled, WAN Access is disabled and so on).

My ISP's Modem/Router is in Bridge mode.

So, I'm guessing the 86U is exposed to the WAN & its firewall is protecting my LAN.

I'm just wondering...

ISP Modem In Bridge Mode, advice?