Huawei E3372h-320 as uplink (UK)
Post for my own reference and for others with this 4G device.
Recent purchase of Huawei E3372h-320 which I wanted to use as cellular uplink on IAP.
Web UI version
The following settings for uplink is what (finally) got it to work.
Tested with IAP305 using version 8.5/8.6/8.7
Pay as you Go SIM cards used for UK were Vodafone, EE and O2.
If my post is helpful please give kudos, or mark as solved if it answers your post.
ACCP, ACCX #817, ACMP, ACMX #294