Queen's Flight High Visibility Day Glow Red Paint

[kenair]

HI, anyone have information as to when the Queen's Flight aircraft were painted high visibility red. I read some where there might have been almost mid air but cannot find that info now and google is not helping so far.

2.Was the high vis paint applied to the Herons done at De Havilland or at a RAF depot.
​​​​​​​ thanks - ken