[just another ref]

Originally Posted by BillyMac

I don't like the word "mistakenly". Neither official mistakenly gave a wrong preliminary signal. That would occur if both thought that it was a charge, and one gave a block signal. They both had what they had. No mistake was made in the preliminary signal. It's not a signaling mistake.

One of the calls was a mistake.

The mistake is not what the signals were, but the fact that both made preliminary signals at all on the double whistle.