Hi-

I am considering buying a ER605 to solve a connectivity problem I have.  Here is my situation:

I have ADSL in my house, and typically get 30Mbps. Sometimes it drops as low as 1Mbps.  There is no fiber option today.

I have a 4G TP-Link router that I also use.  It can get anywhere from 4Mbps to 45Mbps based on weather and time of day.

I have the ADSL running through the 4G router, in Wireless router mode.  Meaning it prioritizes the ADSL and fails over to the 4G when the ADSL is down.  But the ADSL is never really down, it just gets really slow.  I had set the 4G router to 3G/4G router mode, which then prioritized the 4G connection. We burned through our monthly allowance in a few days (my wife does video work).  

I need a way to say "Use the ADSL unless the speed drops below ~2Mbps, then distribute some (all?) of the traffic to the 4G."

I read the ER605 manual, and I don't think this is possible.  Is it?

-Rick