1 wan, still use speed fusion?

I just got off the phone with one of the peplink partners. I told him I want my transit duo to favor my att cellular wan over my Verizon cellular wan, because the att service is less expensive and more forgiving on data limits. If I’m in a location where I find a great att signal and have only the att cell card in priority 1 in the dashboard, he told me to still have speedfusion tunnel active because it would “solidify/ make more reliable” the single att cell internet connection. I thought that u had to have 2 internet sources (wans) to use speedfusion cloud to any appreciable affect. What is the truth?

You can use 1 wan and either do wan smoothing on a single link , under the ? icon, and or use FEC Forward error correction which sends extra data with a checksum.
Now if you are overloading the one WAN connection then it will not help you.

Thanks, Jonathan.
How do I know if I’m overloading the one WAN connection?

If latency is not jumping around , and you see a lot of packet loss on the speed fusion graph.
This is likely an indication you are being throttled, in which case adding redundant packets may make it worse.
You can test traffic both over the vpn and without and see the performance difference.