Does anyone know how many boards you can hook up to a single tp-link?

I will have to set up 25 boards (mine an a friend's). We already have more than enough 8 port usb hubs that work realiably in series.

I have one tp-link and I already flashed the image while waiting, the interface does not give any indication about the number of boards and there are just one set of fields for the configuration so will it just try to set up all the boards it finds with the same parameters?

I have searched the forums but there is no conclusive number, I have seen some people claiming up to 10.