I was a co-pilot on No 103 Hastings conversion course at Thorney Island in early 1963 - ....We were the first course of pilots who hadn't previously completed a tour as second pilots, so the instructors were rather curious as to how we would cope!
Must have taken a while to make that decision then!, I knew someone who in 1949 attended the Hastings OCU from only basic flying training and a multi engine conversion course on Wellingtons, who was placed straight into the LHS as an 'experiment' to see if new pilots could cope with the 'modern technology of the Hastings' and be trained as Captains straight away without being a second pilot.
I am not sure if he was a 'one off' or one of several at the time. He was successful and subsequently flew them for several years.