Differences between FA and SA flags on symdev

Hi I need your help in order to know why a device got WD on all its directors:

This is what happened:

We issued the following commands:

symdev -sid XXXX -file ./devs_to_remove_from_8cB_9cB.out write_disable -fa 8c -p 1

symdev -sid XXXX -file ./devs_to_remove_from_8cB_9cB.out write_disable -fa 9c -p 1

As you can see, we used the "FA" flag instead of the "SA" flag.

The command didn't return any errors, and actually it did what we needed. But we got one device (on a list of 79 devices), that got WD in all its directors.

Obviously the first assumption was that the wrong flag did it, but if that's the case, why none of the other devices was affected like this one?

Thanks
Alex