From the logs, it seems like there is some issue detecting/configuring the network interface of the modem.

(In reply to marius from comment #1)
> From the logs, it seems like there is some issue detecting/configuring the
> network interface of the modem.

There is no network interface in the lsusb listing provided by the reporter, there are 3 serial interfaces:

if#0 utps_modem
if#1 utps_pcui
if#2 utps_diag

A 12d1:1506 without any kind of net interface is unusual for a Huawei LTE device and also remarkable since idProduct in the lsusb listing describes the device as a "Modem/Networkcard". 
The 3rd digit in 4 digit Huawei product numbers denotes the speed where 7 indicates CAT4.
There is no way Huawei would produce a LTE CAT4 device with only ppp modem dialup so I'd say that this dongle has been tampered with, the net interface has been disabled via AT SETPORT cmds.

Marius, could you ask the original reporter about the concerns Lars had?

Also, may be not modeswitched properly? See:
http://askubuntu.com/questions/525965/huawei-e3272-ubuntu

Already did: https://bugs.launchpad.net/ubuntu/+source/modemmanager/+bug/1404068/comments/13

Also usb_modeswitch problem was ruled out. See downstream comments.

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