after I forced my old mac address on /boot/config.txt I couldn’t start piaware service due to invalid feeder id
That is the mistake.
There are two files as listed below, and you got mixed up between the two:
Dont add your old old MAC address in file /boot/piaware-config.text. That file is for adding the NEW long 128 bit ID.
The old MAC address is to be added to the file /boot/cmdline.txt
What is your install?
(1) Piaware 3.5 image (SD card)
(2) Jessie + Piaware 3.5 (package install) + dump1090-fa (package install)
If install (1), use Option-1, Step 5 © (i) of "Bake a Pi"
If install (2), use Option-2, Step 9 (i) of “Bake a Pi”
First remove the line:
feeder-id mac address
from the file /boot/piaware-config.txt, else you will keep getting the warning “corrupt feeder id”