...........am I to believe that BA allows dispatch with u/s autothrust yet the pilots may not have flown with manual thrust lever operation for 3 years ??
You are correct in your belief.
I will add that in the days when there was a usable in house BA intranet forum this whole topic was often the subject of lively debate (usually led by our Airbus colleagues). Management were consistent in voicing their belief that the current policy was a "good thing"