This is possibly the worst docu-drama ever made. It lacks coherence, contains ludicrous acting by professional actors and by real people (Brian Miche, Malcolm Sargent for example to name but two.) Settings are artificial (even for 1943) with a distinct lack of continuity.
The direction is sluggish and lumpy (rather like yesterday's cold porridge) with little thought for lucidity or verisimilitude.
What saves this mediocre film from damning mediocrity are the historical extracts of the LPO in action with notable conductors like Constant Lambert, Warwick Braithwaite and Sir Adrian Boult. Recommended then for lovers of music but not for lovers of film making.