How to change Sierra Wireless preferred firmware

[Tom Isaacson]

I'm using a Sierra Wireless WP7610. Because we can switch SIM cards we
need to be able to set the preferred firmware. Sierra implement this
using the AT!IMPREF command:
AT!IMPREF?
!IMPREF:
 preferred fw version:    02.28.03.01
 preferred carrier name:  ATT
 preferred config name:   ATT_002.071_000
 preferred subpri index:  001
 current fw version:      02.28.03.01
 current carrier name:    ATT
 current config name:     ATT_002.071_000
 current subpri index:    001
OK

I asked them how I could do this via QMI and got the reply:
"'at!impref' function call is SDK function SLQSSetSIMBasedImageSwitching."

But is there any way of doing this via qmicli? If not is there an
example on how to write an app with QMI?

Thanks.

Tom Isaacson