I just bought my new Capo 2 weeks ago and I have the same issue also. My bike dealer has reported it to Aprilia, and am waiting on them to send over a new dash board (think thats what you call it, lol) then they will connect and install it. Can't wait! Tired of using the odo.
Good to know its a known issue and that I'm not the only one. Lets see how long this takes.
The upper fuel level sensor is a known fault on these. Should be changed under warranty. The lower sensor will still operate and show fuel light and reserve function.
There is much more activity and information over on the A1 forum, check it out too.
Changing the dash will not cure it, it is the level sender in the tank at fault.