so they'll transmit power through an unpowered EBx to everything linked by aquabus?
The only thing that gets powered by the AB are the modules themselves. Outlets on an EB8 need local power for that EB8. One EB8 won't power the outlets on a different EB8. Your idea of the UPS and the 12v supplemental power is perfect, just remember that your router and modem must be on the UPS as well if you want to get email alerts.