SBUS problem with Arduplane

Hopefully the right place to mention this issue:

My Setup: Futaba T14SG + R7008SB in mode B connected to Pixhawk 1
Arducopter 3.3.3: works with 12 channel FASSTest and works with 14 channel FASSTest
Arduplane 3.7.1: works with 14 channel FASSTest, does NOT work with 12 channel FASSTest

I talked to a Futaba service technician and he said:

  1. If you use SBUS, than use 14 channel FASSTest, DO NOT use 12 channel FASSTest ! Sooner or later you will have a problem using the 12 channel FASSTest SBUS output.
  2. Never use SBUS 2 for any gyro stabilization system unless it is explicitly allowed !