Serial baudrate won’t operate at 1200

Cube Autopilot
1

I’m using a Cube Orange with firmware Arduplane 4.5.7 and configured serial2_baudrate=1200.
It seems the cube won’t go down below 2400 as I’ve seen when testing the signal with an oscilloscope. When configured 1200 it still operates electronically at 2400.

2

@Michael_Oborne

3

@sidbh any reason for a 2400bps baud rate min?