So I had the M5 mesh working wonderfully.  Then my ISP sent me a new modem.

The new modem is a gateway so it has built in WiFi that cannot be disabled.  It is a UBC1326 with Optimum/Altice.

The built in WiFi isn't giving adequate coverage throughout the house.  So I plugged in the M5 and it worked great, but has frequent drop outs.  We lose internat access for a few minutes many times during the day.  My research shows that there is a conflict with the two WiFis?

I can't disable the UBC WiFi.  I did get an Optimum tech who claimed to have disabled it, but then another tech reset the modem and I guess it is back on.

I'd very much like to use the Deco mesh.  So, I could request a new modem that isn't a gateway, but the only other one they offer that fits my needs is the Arris 3402.  That allegedly has the Puma 6 chip defect and I have been warned away.

So finally, I think there is a way to set up the M5 as an access point?  How would that work and is it something I should try?

Thanks