Some comments about Elevon type A/B.
1) Reason why, both servos were not mirror imaged(flipped, rotated? when installed).
2) If it doesn't work, I always reverse leads going into the receiver. Reason being, I wrote a mix off elevator one time and it didn't work due to going to Elevon B, it now was aileron.
3) After you switch leads and now the reverse happens, it still doesn't work.
4) Here is the key- you need to go in your transmitter to servo reversing.
5) Say-- turn on the reversing for aileron and move the controls. If it is right, fine, you solved it
If it is still wrong direction, reverse that switch, back out of aileron. Now, go to elevator servo and reverse direction for that servo. Move controls and that should be right.
6)Concept----You must change direction of only one servo, that being the one that has the wrong direction.
Happy trails!!!!