Brent East by-election

I've just had an email from the Liberal Democrats, saying that the Brent East by-election (called after the death of Paul Daisley MP) is likely to take place on July 17th. The writ for the by-election hasn't been moved in Parliament yet, but that seems a likely date (though I suspect it could be the 24th, instead, depending on when the writ is moved) - I suspect the Government wants to get this over and done with as quickly as possible, and not leave it hanging over the summer.