I have the following setup:

S900
A3 Pro
E1200 Propulsion
Lightbridge 2
X5 Camera (Using M600 Mounting bracket)

My air unit on the lightbridge 2 fails every time I try to update it, however even though it says it has failed, when I go to check its version number it shows it has the update installed.

My issue is that I need to get it onto v1.1.40, however if I upgrade to 1.1.40m it also says the current version is BOTH 1.1.40 and 1.1.30.
In the same manner if I upgrade to v.1.1.30, it also says 1.1.40 is current also, both at the same time.

I cannot link my remotes, and I cannot connect to the aircraft.
I recently updated the X5 via the SD card with the inspire X5 Pro update also.
Does anyone know where I can download a standalone version of the LB2 updates? (1.1.40) - Not via the assistant software.
Any ideas?

Have you tried downgrading the LB 2 firmware via the Go App and then re-upgrading? It worked for me when I hade upgrade problems.

You have to downgrade and upgrade them both while they are not connected to each other or the aircraft.