I believe Support can change WAN2 so it's treated as a cellular connection, and thus will follow the usual cellular-only rules.  Haven't used it myself to say for sure, though. ... View more

I'm using Cradlepoint CBA850s to add a 3rd WAN option.  There's a nice walkthrough on the Cradlepoint page on how to set up Ethernet IP passthrough on the CBA850, which can then be configured to failover to LTE if the Ethernet is down. Plug the CBA850 into WAN2 on the MX, and you're done.   https://customer.cradlepoint.com/s/article/How-to-Configure-Inline-Failover-on-a-CBA850   It's all managed through their NetCloud dashboard, so I can still manage everything remotely just like I do with my Meraki devices. ... View more