Hi @Thomas_Hudson . It’s absolutely possible as that’s probably what you have instructed your router to do via outbound policy. It’s likely load balancing and alternating outbound connections between your two WANs – the default behavior.
You may want to take a look at your firmware manual for a discussion of the various policies available. Here was one place, among many, where the topic has been discussed here on on the Forum.
You are essentially implementing an “enforced” outbound policy when you unplug one of your WANs. I might suggest you try something like the following example. In this rule all traffic headed to mywebsite.com will use Comcast if it is healthy and if not, will be directed to the 5G Max Adapter with a TMO SIM installed.
It’s worth “getting to know” outbound policies as this is a really powerful feature of Peplink routers. One final note: The rules are interpreted “top down” so as soon as one rule “fires,” or its conditions are met, the ones which follow are ignored.
Final gratuitous comment: The Balance 20 router is a good product but it likely cannot handle the throughput your WANs offer. It may be time for something a bit faster. ;<)