LoRa-E5: Reconnect to network after powerdown

Hi,

I’m working on a low-power device using the LoRa-E5 module. I would like to power off the Lora when it’s not needed ( I’m aware of the deep sleep feature of the module, but power off offers better consumption).

Is it possible to connect a first time in OTAA, and then connect in ABP mode after a power-down, using the keys from the OTAA sessions?
Or do I have to use only OTAA or only ABP?

Things that I tested:

  • OTAA only --> works fine
  • ABP only --> works fine
  • JOIN OTAA / restart / change to ABP mode and send a message --> Not working
  • sends a message in ABP (ok) / JOIN OTAA / restart / change to ABP mode and send a message --> Not working

Thank you in advance for any help