There is a sign-up page to be notified when this is available on the Airstream website.
What it appears is this will not be available until late October.
It is for both AS with and without built in wifi hotspots.
If your current AS does not have factory installed wifi hotspot, then the dealer will be able to put one in and place a wifi antenna on the roof.
No mention of owners buying and installing the wifi hotspot themselves.
No mention of owners currently using their smartphones as a hotspot.
I will post when I have been notified of the 'fine print'.
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As an aside, I know it irritates some forum users when a subject gets surfaced that (according those users) has already been discussed elsewhere on the vast forum. It is huge.
I spend my time on the 22FB sub and while I do check the searches if appropriate, I still feel surfacing a subject on this sub-forum is both appropriate and helpful to others who do the same as I.
The forum 'police' who always show up here to remind us of the search function and the fact that our questions/help is redundant need to think beyond their role of policing and more in terms of helping others. IMHO. (written in the spirit of honest forum improvement).