Yes. It sets up the British units on turn one by changing the formation orders (Advance, Attack etc ... limit losses, ignore losses etc) and the objective tracks. It is a way of randomizing the behaviour of the British PO.
The problem is the wording in the introduction. It reads as though you must let the computer play the British first turn. In fact, you can ignore that if you playing PBEM, you can ignore that if you are playing the British against a German PO, and you can ignore that if you are playing the Germans against a British PO (well, not exactly ignore it but you will have it set up to play the British PO anyway).
The only occasion when you might(?!) need to ensure that the British PO was set up correctly would be, as you say, if you intend to play some of the game in hotseat mode and then change to let the computer play the British side. In this case, you might(?!) need to let the computer play the British PO on the first turn.
However, if it is truly one's intention to play part of the scenario in hotseat mode, then the randomizing of the British formations might well be inappropriate. In short, I can't think of any legitimate reason for putting that instruction in the introduction. As far as I can tell, it's only purpose is to confuse people. And some of us are confused enough as it is.
Yeah, the wording of it was poor. :D Good job.
To repeat history in a game is to be predictable.
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