Here is the newest (as of this comment post date) firmware for just the modem and the simplest way to update it directly from a support person from GLiNet directly from another thread that they were helping me with. [quote="ywp, post:10, topic:37128, full:true"]
Access the background of the router using ssh
ssh root@192.168.8.1
1.mkdir /firmware
2.cd /firmware
3.wget https://fw.gl-inet.com/download/RM520GL-modem_firmware/RM520NGLAAR03A03M4G_01.201.01.201.zip
4.unzip RM520NGLAAR03A03M4G_01.201.01.201.zip -d RM520NGLAAR03A03M4G_01.201.01.201
5.QFirehose -f RM520NGLAAR03A03M4G_01.201.01.201
6.reboot
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