Not only is my Mobley (in a separate router) still working, it appears to be working better than ever. I wonder if 3G was available the software picked the 3G service but now is being "forced" to 4G. I love my Mobley more than ever. I thought I would give this Cudy AC1200 dual bank unlocked router a try. It worked every bit as well as my older Netgear hotspot but I am not sure it worked any better but the addition of Ethernet ports has added a couple of additional options.
Since the "3G shutdown" (if it happened) my speeds are amazing and performance from the streaming services I use has dramatically improved. Pretty happy with unlimited AT&T for $23/month. Sorry to say that if you missed it a few years back, the option is gone forever.
Speedtest