RE: Multiple servos in an Ultimate
That's not normally how bipe ailerons are mixed...
You plug the left wing servos into a "Y"
You plug the right wing servos into a "Y"
THEN mix the two using the Aileron and AUX channels.
On Futaba I put the right aileron in the aileron channel (1) and the left aileron in the Flap channel (6)... then enable flaperons.
If you have to reverse a servo (usually a pair on one side) simply reverse the channel they are plugged into...