How to use a MGTS router without MGTS?

Question

network hardware

Good afternoon! There is a MGTS router (from gpon) sercomm rv6688bcm.
Can it be used with regular cable internet?

Answer 1

Thoughts out
loud 1) Can this box be changed into something else? openwrt/ddwrt etc.?
2) Is it possible to tear off the port from the "lan" switch group on an alternative firmware?
If the answers to both of these questions are positive, then you can use it with any ethernet provider.
But most likely it is impossible to fill in an alternative firmware there and / or it is stupidly absent.
At one time, the question was also raised "is it possible to use the adsl modem as a router for the ezernet". It often turned out that the SoC and the strapping allow this, but there is no firmware.

Answer 2

The same question interests me. Openwrt would like it

Answer 3