Hi Dave
There was an article on 228 OCU published in the January 1967 edition of Air Pictorial written by Roger Levy. It covered the period 1965/66 and might help with some of your queries.
Apparently each pilot logged 50-60 hours at Leuchars with average sortie time being just over an hour. Navigators logged around 45 hours. In addition as much time again was spent in the Javelin 9 simulator. The first course started on 1/6/65.
The article states that the 11 Sqn 'shadow' role was adopted 'mid-summer of last year' so presumably mid 1966. Markings comprised 'a pair of buff-coloured eagles, each with yellow bill and feet, set against a white disc'. These markings were also applied to the three Canberra T.11s operated by the OCU.
Hope this helps
Peter