I can feel your pain, Cal. I am going to face the problem of data upload to the the cloud or whatever on some projects that I am contemplating. I have a Mayfly water sensor on my property and the 2G is working fine. Shannon has a small box that does a 2G site survey that we used before installation of SL149
I think the larger concern will be how to upgrade all the existing Mayfly’s using 2G when that service goes the way of the dot-matrix printer!
I got some input on this question from some colleagues and in summary 3G and 4G will be overkill in terms of data rate so it would be expensive. The other option might be ORBCOMM which is a low data rate store and forward system which might be more affordable.