Searching for api to switch between 4G and WAN

[edsub]

My B315 has the option to 'failover' from internet traffic the 4G connection to a WAN connection (or the other way around).
This failover apears to be manual.
I am searching for the api to trigger the switchover from 4G to WAN and vice versa.

Use case:
I only have 4G
The SIM in my B315 has a limited data amount (which is the max of my provider).
Now I want to link another modem to the WAN port with another SIM in it.
Now when the data amount of the B315 SIM is used, then I want to programmaticaly switchover the internet trafic to the WAN port (and thus the other modem/SIM).

I prefer not to use the B315 GUI as
a. I use the B315 as a bridge (GUI not available)
b. I want to be able to do this from the internet as well (GUI not available)

.

[Salamek]

@edsub This library uses same REST endpoints as a modem GUI, so... and i don't have any Huawei device with WAN to test/implement failover endpoints