OTA error at nvidia-l4t-bootloader update from JetPack 4.3 to JetPack 4.4

As requested by @ WayneWWW

Copied from topic JetPack 4.4 Developer Preview - L4T R32.4.2 released

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After following To upgrade to new minor release @ Welcome — Jetson Linux<br/>Developer Guide 34.1 documentation I just encountered an error at the end of the dist-upgrade process:

Setting up nvidia-l4t-bootloader (32.4.2-20200408182156) …

3448-300---1--jetson-nano-qspi-sd-mmcblk0p1
Starting bootloader post-install procedure.
ERROR. Procedure for bootloader update FAILED.
Cannot install package. Exiting...
dpkg: error processing package nvidia-l4t-bootloader (--configure):
 installed nvidia-l4t-bootloader package post-installation script subprocess returned error exit status 1
Errors were encountered while processing:
 nvidia-l4t-bootloader
E: Sub-process /usr/bin/dpkg returned an error code (1)

and

xxx:~$ sudo apt-get install nvidia-jetpack
Reading package lists... Done
Building dependency tree       
Reading state information... Done
nvidia-jetpack is already the newest version (4.4-b144).
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
1 not fully installed or removed.
After this operation, 0 B of additional disk space will be used.
Do you want to continue? [Y/n] y
Setting up nvidia-l4t-bootloader (32.4.2-20200408182156) ...
3448-300---1--jetson-nano-qspi-sd-mmcblk0p1
Starting bootloader post-install procedure.
ERROR. Procedure for bootloader update FAILED.
Cannot install package. Exiting...
dpkg: error processing package nvidia-l4t-bootloader (--configure):
 installed nvidia-l4t-bootloader package post-installation script subprocess returned error exit status 1
Errors were encountered while processing:
 nvidia-l4t-bootloader
E: Sub-process /usr/bin/dpkg returned an error code (1)

Did someone encountered this error before, and if so, what was the solution?

I have to upgrade six boards. First dist-upgrade one was successful. The above encountered was my second board.

And my third + fourth board:

Errors were encountered while processing:
 nvidia-l4t-bootloader
E: Sub-process /usr/bin/dpkg returned an error code (1)

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If you issue sudo apt autoremove the following error message is displayed/returned:

xxx:~$ sudo apt autoremove
Reading package lists... Done
Building dependency tree       
Reading state information... Done
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
1 not fully installed or removed.
After this operation, 0 B of additional disk space will be used.
Setting up nvidia-l4t-bootloader (32.4.2-20200408182156) ...

3448-300---1--jetson-nano-qspi-sd-mmcblk0p1
Starting bootloader post-install procedure.
ERROR. Procedure for bootloader update FAILED...............................................] 
Cannot install package. Exiting...
dpkg: error processing package nvidia-l4t-bootloader (--configure):
 installed nvidia-l4t-bootloader package post-installation script subprocess returned error exit status 1
Errors were encountered while processing:
 nvidia-l4t-bootloader
E: Sub-process /usr/bin/dpkg returned an error code (1)