Thanks to
@Tech9 for the super helpful description of Dual WAN.
I called the copper wire company today - they directed me to their 5G service. After some pushing, they admitted there was a 6mb copper wire service - but then checked and clarified it was only available for their standard definition pay tv service
So I think this means either 5G or a creaky old DOCSIS system - most likely 5G then since I'm in an area with good coverage and close to several towers
I've ordered the ER 605 and step 1 will be to get this working with my current 5G WAN and wifi router
Step 2 will be to get a second connection (with a 14 day free trial period) and see how this goes
Step 3 will be to upgrade the wifi - will take
@degrub's "sit on the couch" suggestion in the interim! I'll no doubt have plenty of questions about this in due course. Hopefully not too many about the Dual WAN.
Will report back and let you know how I go. Thanks so much for all of your help. Really appreciated.
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if only!
In some Asian cities the buildings are so close that one guy with a better router may be enough.
FYI - I'm living in a big city Tokyo / Singapore style place, not really a jam packed village!