No LTE connection to TTN

RAK7258 didn’t switch to LTE when no more connection, i can’t use LTE as backup (or as main) channel

RAK7258LTE, US915, RAK7258_LoRaGateway_1.1.0063_Release_r205, packet forwarder to TTN

LoRa® Server:
Packet forwarder to TTN

Hmm …
I have more and more questions as I research RAK7258 (LTE).
Firmware RAK7258_LoRaGateway_1.1.0063_Release_r205
My gateway is connected to TTN and works great when WiFi or LAN connection is lost. He “silently” switches to what is available.
BUT. In the case when I turn off WiFi and then turn off the LAN gateway LTE connection DOES NOT SWITCH.
At the same time, the LTE module works and is registered in the network.
When the gateway is rebooted without WiFi or LAN connection available, the gateway does NOT connect to TTN and (of course) does not send packets.
Where and what settings do I need to check / correct to get a working connection via LTE?

UPD.: I really don’t understand why release gateways like RAK7258, in addition to calling it “commercial”, if instead of working normally with the normally described settings, users have to sit all the time on community pages, support and forums and look for information bit by bit?
Why is there not a word in the documentation on how to set up LTE or run minimal diagnostics?
Why install a module with a cost as a half-gateway, which does not work by default out of the box, and whose functionality is restricted?
Why restrict access to installing packages if the firmware is based on OpenWRT?
To be honest, this is the most problematic piece of hardware I’ve encountered in the last 10-15 years …