Replace yellow D2 with red colour

Problem environment

The choice of colours in light emitting diodes allows for good recognition of runtime states.

Steps to reproduce

1. Observe LEDs in design
2. Leave the green colour
3. Replace the yellow with red

Expected result

D2 is specified as a red diode.

Actual result

D2 is specified as a yellow diode.

Severity level

This is medium priority because runtime benefits with little extra effort.

The LED choice has stabilised, with green indicating power, red indicating radio operation, and yellow indicating a user function.