

Not really, under an area blackout the fiberoptic transmitters will stop working, so you won’t be able to reach other areas/nodes even if your equipment has UPS power.
But, in general, the idea of a UPS is to provide enough supply to allow for an orderly shutdown, preventing equipment damage or data loss. Its not meant for long term operations.
For infrastructure and other critical applications, the UPS is designed to give you enough time to go start the diesel generator, and continue the operations.
As a bonus, some UPS have filters to ensure that delicate electronics get a nice, clean power wave. This is usually the case in UPS for data centres.
Btw, how are you liking down under’s “revolutionary” idea of Fibre + Copper? Is it as bad as it sounds?

Have you considered a torrent based solution?
Setup a torrenting server hosted online somewhere with fast speeds (e.g. Netherlands), sync it with gdrive, create a torrent for your books, and “download” your books to the toreenting machine.
This approach won’t help with upload speed, but it should help with reliability/continuity. As long as you seed from your home computer, your books will eventually make it into your gdrive.
Although with this setup it might be easier to just torrent the ebooks to the online server from sources other than yourself.