[LEDE-DEV] LTE modem with QMI protocol

[ivan]

I have a linksys E4200 v1 router with an LTE usb dongle zte mf821 (branded
polsat).
I'm connected on WAN network through the LTE dongle using QMI protocol
(qmi_wwan), all working fine but I have an issue that happens on both
wireless and wired network: sometimes browsing over internet the connection
on browser freeze. 
I found this article related 3 qmi_wwan bugs that could be the cause of my
issue, and if I understand well they has been solved into 3.8 linux kernel:

http://www.mail-archive.com/linux-usb@vger.kernel.org/msg19917.html

Could you confirm me if these issue could be the cause of my problem?
if no, could you help me to understand what could be the cause of my issue?
thanks
Ivan