Chillimonster.
I wasn't suggesting that ATC didn't know about the slot, I realise they do. I was suggesting that the EZY wanted the tower to know they'd be ready for an immediate departure so that the tower could then make their decision on the order of events, rather than the tower planning on letting the EZY go first only to find out that the cabin is not yet secure and it cannot accept the clearance.
In my experience the ground and tower controllers are excellent at sorting slots out. If they realise you're not quite going to make it they'll apply for a 5 minute extension, they plan well to make sure that aircraft on slots are not stuck behind non restricted aircraft at the holding point, and what's more once they've given you a start clearance they'll normally launch you off regardless of whether you are more than 5 minutes early or greater than 10 minutes late. I have the utmost respect for ATC and I think they do a superb job.
What I was really trying to point out for the benefit of those thinking "so what if the EZY misses it's slot" was that the subsequent delay could be a long one possibly causing the EZY to go back and get more fuel. This is why the pilot would be very keen to make sure the tower knew he was ready.
I guess it’s also possible that the captain asked the FO to tell the tower they’d be ready for an immediate departure but because the FO never used those words the captain wasn’t happy that the message was understood so asked the FO to tell them again using the exact phrase. Who knows, perhaps it was just a rude impatient FO, but that sort of personality doesn’t really sit well with the EZY culture and I’d be surprised if it would get through the selection process.
SW