I saw this and made a booking today but this is the first I have seen of a promo code.
I may need to cancel and rebook.
EDIT - I just did initiate a booking and when I pasted that code (above), it asked me for IATA travel agent login. The AC website details about the promotion do not say any code is required. So
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screen shot of promo
And, oh, I tried it again and the code worked.
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