Thanks!
I looked at that page you suggested, but it doesn’t fit my case for 2 reasons:
I don’t own the modem I asked about. I am considering buying it.
I don’t have a wired internet connection at all, so your remote-connect procedure wouldn’t work.
I was hoping that Peplink would be able to comment on whether the U772 or any other of Sprint’s current offerings has been tried since the last time the “Supported 3G/4G LTE USB Modem” list was updated.
As I said, for now I’m connecting my aging AirCard 771S to the Surf’s USB.
I hope that one of Sprint’s current potential replacements will be on your supported list soon.