I noticed the serial number on the unit and the box are the same. I wonder if that means every unit has the same serial number or there is some actual QC.

The handbook is a basic two sider but makes sense at least.

The 18650 cells are made by a company called Wintonic who I've never heard of and there doesn't appear to be much info regarding their cells so these will likely need to be replaced but they do at least appear to have the stated capacity e.g. not massively overinflated.

Think I’d prefer LFP chemistry instead of 18650s but they don’t seem to make any products like this with them unless you go for a power station type device.

It is running my Proxmox host (OPNSense) and ONT fine.
I will need to make up a cable for the phone which uses RJ11 for power and work out what to do with the AP and switch.
I could try running the AP through the UPS as it has a port for this.

https://i.imgur.com/1UUEX1O.jpg

They will probably be rewraps of another brands cells as there aren't that many manufacturers.
In my experience Samsung, Sony and LG make the best cells.
If you want to get them from a UK supplier look at vape sellers like the one below.

Link

Thanks
Dan

Yeah. Fogstar come highly recommended. I know of them from ebike forums.

The approach I take is to stick a PoE switch in and then power everything off the switch. Then protect the switch with an old beige APC Back-UPS mi models. You can get them quite cheaply off eBay. Those things are built like tanks and just last forever, accepting the batteries do need replacing from time to time.