Automating FOTA Flashing for 20 boards of nRF52840 DK using BLE

I am working on automating the FOTA flashing process for 50 PCA10056 (nRF52840 DK) boards using a Python script. The goal is to efficiently flash firmware onto multiple boards simultaneously while ensuring reliability.

I have already tried using nrfutil, but I encounter the same error as described in Case ID: 256309. Additionally, mcumgr has never worked for me.

I would like guidance on:

  1. Best practices for automating FOTA updates on multiple nRF52840 DKs.
  2. Recommended tools and libraries (nrfutil,or other alternatives).
  3. The best command to use for this operation.
  4. Handling potential issues such as connection stability and flashing failures.
  5. Any existing scripts or references that could help streamline this process.