If you find that the sub PIB is coming up on the same address as your OA payload (I think you said it's coming up on 0x100), you can change the address to 0x800 as follows:

1. Turn off the OA payload
2. Turn on the payload with the sub PIB and wait for it to enumerate
3. Send a Write Console Script to address 256 (0x100) function code 0 with the script set to "PIB -b 8" (this should be acknowledged)
4. Cycle power to the payload with the sub PIB and verify that it enumerates on 0x800 (2048)
5. Power up the OA payload and verify that both payloads are accessible (send a command to each one and verify response.)