Do we know what the latency is yet ?

If you are asking for the latency of the controller to the receiver with the OSRC setup, standard xBee latency should apply, as that is the module used. I believe it is around 11ms, but correct me if I am wrong. If you are using your own module, then it is the latency of that specific module...

the latency from the optical encoder read to action on the output of the aircrafts Xbee

No, the latency from the time encoder has read the info to the time the motion is executed, using the RF Cloud and the xBee module has not been measured. So far had no reason to, since if there is any then i can't feel it.

Perhaps when there is some free time and the question still exists, i shall take the time to measure it.