It definitely won't be true for all mobile operators. I'd be a bit surprised if it's even true of the original one at this time. The software seems to be from t

It definitely won't be true for all mobile operators. I'd be a bit surprised if it's even true of the original one at this time. The software seems to be from two years ago, and this would have been a stunningly generous policy by the standards of that time period -- the description says that they were only blocking TCP port 80! (Already 10 years ago the main hole open in captive terminals was properly formatted DNS requests/responses, so you'll find a lot of ip-over-dns tunneling projects from around that time).