Most FBW Airbus either have an active aileron system fitted as standard, or on some types as an option. Know as Manoevre Load Aleviation (MLA) it's controlled by the FBW electrickery. It's there, and that's all the manuals say about it - so don't ask the pilots how it works. The ailerons on the A320 series also droop a bit with full flap to add a little more lift, but this reduces aileron effectiveness.
My company removed the MLA on it's Airbusses as it cost more than it saved.