Jeremy Corbyn lets off Labour's Brexit rebels with a written warning

But frontbenchers will be sacked if they defy the whip again, say party sources as MPs Andrew Gwynne and Ian Lavery are picked to lead election campaignsJeremy Corbyn has let off the 10 frontbenchers and three party whips who defied the party line and voted against Brexit on Wednesday night with a formal written warning.The Labour leader had suggested he would be “lenient” in dealing with the 52 Labour MPs, many of them from strongly remain-voting constituencies, who refused to toe t