re: this talk of DNS from sammo…I have tried every possible combination of settings in the main Admin Panel GUI that involve DNS including:
DNS Rebinding attack protection - tried both enabled/disabled
Override DNS settings for all clients - tried both enabled/disabled
DNS over TLS from cloudflare -tried both enabled/disabled
Manual DNS Server settings (I have not touched this one as I have nothing manual to input).
What other DNS setting is there for me to try outside of LUCI?
No matter what setting I use above, with AR-750S v3 firmware the captive portal page will not ever appear on the attwifi or hhonors networks that every Hilton and Hilton brand hotel property use when connecting an iPad or iPhone directly to an AR-750S that is itself connected to the attwifi or hhonors network. This is one of the most popular chain of hotels in America and includes Embassy Suites, Homewood Suites, Doubletree, etc, so I think for a travel router to be useful to your average person it must work with this brand.
Captive portal page pops up immediately on both iPad and iPhone if connected directly to the attwifi or hhonors networks without the AR-750S in between. So then I have to get MAC registered via iPad or iPhone and then clone MAC on AR-750S to make the AR-750S work, but I do not think this should be necessary.
As stated before I have vpn/wireguard off for all of this. I am currently on 3.003 firmware but also saw this on 3.001 and 3.002 versions as I tried backleveling in case that helped (it did not).
I hope that @alzhao stays at or nearby a Hilton property for CES 2019 in Las Vegas, then maybe he will observe this same issue and I can have hope for a fix! Or maybe try the Hyatt in Beijing, as @guwester experienced, because I believe it is likely the same issue.