Ah BEags, how well I remember such days! Only keen types had walk on or speaking parts on the parade, the shags formed a "supernumerary flight" traditionally positioned "behind the flag". A motley group of ill-fitting No 1s, topped by aged Bates hats, more green than blue, and probably stuffed with newspaper to regain some shape.....
And speaking of lunches, I actually went to a "practice lunch" once in advance of a Royal visit (Charlie's Aunt IIRC). But it was foodless and drinkless! Staish and PMC so worried about a serving c*ck-up, that empty plates were delivered to all particpants, stewards wandered around with empty bottles, empty plates (and appropriate irons) collected - to be replaced by further empty plates of a different size!!
And you tell that to t' young folk o' today, an' they'll not believe yer!