Device in question - Huawei HC156 (what it says on the packaging)/HC1260 (what it says in lsusb).
I CAN connect to the internet with it, but I can't change modes between 1x, EVDO, Hybrid. The option to do this, it seems, is available only in the Windows application bundled with it, and I have absolutely no clue on how to do that on Debian.
So far, the solution has been to start Windows, use the app to change mode preference. The change then shows up in Debian. Is there no way to do it from Debian itself?