SCR50AXE sending internal ARP requests on WAN interface

Hello, I've just captured some traffic from the WAN interface of my SCR50AXE device. One thing seems very odd and that is that the device is sending ARP requests of internal VLANs on the WAN interface. Sending ARP requests on a completely different Subnet makes no sense in itself, but sending all ARP requests from all internal VLANs on the WAN interface is really not great for security with no benefit I can think of, so I guess this must be a bug. I'll attach a screenshot of Wireshark. The 192.168.72.0/24 Network is on the WAN side of the SCR50AXE (WAN IP: 192.168.72.100) and the Networks 192.168.172.0/24 and 192.168.174.0/24 are two VLANs on the LAN side. I captured this on the WAN Port.