I need a Gateway that will work with AT&T LTE in the US. I'm planning on using it with Zabbix to send more urgent messages to a couple of people, we'd like this to work, even if the network is down. This is why we've decided to use a actual LTE device. Zabbix is running on a physical box, can we do direct AT commands through the serial RS232 port of the RUT955? I know there might be more ideal devices, but it doesn't seem that any support all the AT&T LTE bands other than the RUT955. Thanks in advance!