The BBC Scotland website currently has an article, "Irn Bru sales go up after new recipe introduced", indicating that Barrs have just had their best-ever year of sales.
Specifically, the sales numbers referred to are those up to the 27th of January this year (see the twelfth paragraph). The problem with that being that the recipe change occurred in late January of this year - indeed, I purchased at least some original Irn Bru even in February of this year.
So, in fact, this is a story about Irn Bru sales going up before the new recipe was introduced.
Ultimately, this is a story that doesn't really matter - Barrs will no doubt be looking at the up-to-date sales figures and will make a decision based on the reality and not the friendly spin the media has chosen to give them.
But it raises (again) a question: if they're willing to lie to you about this, what else are they willing to lie to you about? (Well... I suppose it's possible that this is just gross incompetence on the person who wrote the headline. I'm not sure that's really any better.)