FS#4003 - VLAN interface drops default gateway, prompting interface restart

[openwrt-bot]

bitshiftnetau:

Device: raspberry pi 4b+
OpenWRT: SNAPSHOT r17101-f4e3ff5b07
Steps:

1. setup rpi in AP mode
2. setup VLAN interface on br-lan and set the protocol to "DHCP client"
3. use the firewall rules to route from wlan to br-lan
4. wait an unspecified amount of time

Eventually the interface will drop the default gateway for some reason, reflected in the internet access on devices connected to the wlan. Restarting this VLAN interface will instantly fix the problem and connected devices can access the internet again.

See attached config