Did the election date change because of Guido, McBride and Smeargate?

Offered without comment.

A communiqué sent from the US embassy on April 24, 2009, reported that the then prime minister had planned to go to the country when Labour rose in the opinion polls after the G20 summit in London.
But the plan was called off after it emerged that Damian McBride had sent emails to Labour aides containing unfounded allegations about the personal lives of senior Tories. Mr McBride was forced to resign.
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The cable, passed to the Daily Telegraph by WikiLeaks, went on to describe Mr McBride in unflattering terms: “Unpopular within the Labour Party according to our contacts, and a particularly unpleasant person based on our own experiences with him, McBride was one of Brown’s closest advisors, having followed him to No. 10 Downing Street from the Treasury.”