I know this is old thread but my $0.02.
Family and I have been going to Harborside last 4 years, last trip was this March 14-21 2020. This was the first time my kids were able to use our cell phones for internet. Of course there were no Cruise Ships in port....
Atlantis and Harborside WiFi is like $28 per day, it covers the entire resort.
There are several Free WiFi spots on property. The Royal and Harborside main office are 2 that I know of.
T-mobile says you get 4g but BTC knocks you down to 2g\edge.
Verizon you will need to buy an international plan I believe.
I think I am going to invest in a prepaid SIM card with BTC or aLiv and use a Hotspot device, I read a lot of boaters do this. But I think you need to re-activate the prepaid sim every 6 months or something like that. Otherwise you need to buy a new Sim, when I figure that out I will post about it.
Also note this year we did get free WiFi in Atlantis, its seems their wireless controller was having issues (I'm in "IT"). My daughter found the flaw when the login page would fail to load (I say she "found the flaw", I just think she kept trying to connect to any wifi spot).
We all did the same thing and had WiFi for almost the entire week.
It made my afternoon Covid-19 conference calls more affordable.