Flashing addressed MCU thru RS485

Hello all.

First of all, I’m still awaiting for my Arduino UNO to arrive.
I just like to think ahead and find as many ‘do and don’t’ as possible.

It seems already possible to flash a MCU thru RS485.

I have Googled a few times now, but I can’t seem to find to do so with addressing.

I understand that the bootloader should ‘know’ what address it has.
I guess this number could be read from the EEPROM.
But also, the software that uploads the firmware, should ‘know’ to which address the firmware should be sent (or better: by which address the firmware should be received)

Has anyone done this or could point me in the right direction?