That's the one!
The problem of apparent non-connection stems from the way that devices determine whether or not you are connected to the internet - you were connected but since every attempt to get anywhere was being redirected, all the devices/apps trying to lookup their own 'internet detection' page did not get it and declared 'no connection'. In extreme cases this might prevent a web browser working but it shouldn't. Many apps on the other hand just ask the device's internet detector whether or not there is any internet, and stop when they are told 'no connection'.
[ Additional Splaining which may help but is probably just an exercise in self-indulgence : The devices/computers do lookups for e.g. captive.apple.com, mtalk.google.com, teredo.ipv6.microsoft.com but the filtering system returns a result that takes you to vodafone.co.uk and the choice-page so the device sees "choice required" instead of "iWelcome. You are better than everyone." or "google is your friend. google loves you. google sets you free if you do everything google tells you" or "You say you hate us but here you are still using Windows several versions later, take the plank from thine own eye etc.", in no particular order 😉 ]
[ confessing that on this count I am 1.5 out of 3 guilty, google use is with care and on an android device with annoyance at having to turn everything off, but totally 100% guilty of continuing to use Windows ]
E&OE 😁
