At the last minute if at all possible. The government isn’t even close to ready, but the people have spoken. The Brexiteers want to get on with it, and May promised that they’d pull the trigger by the end of March, but parliament’s the one that has to make it official, and they’re not interested in keeping May’s promise. Still, if they drag too much, the people will remember. Unless they come up with a brilliant excuse to continue the stall, it’s a near certainty they’ll do it by July.