I was at a Sadler's Wells production yesterday and took the opportunity to talk to someone in person about Jon's show. At the ticket desk the woman I asked knew nothing, but overhearing, another woman at the desk called me over and said that the latest she knew was that the contract details have yet to be finalised, but are in the process of being ironed out. She then spent several minutes at her computer to see if there was any other news or updates in their system, but that revealed nothing. She then gave me an email address for their events department and said I may be able to get more info from them. I'll email them soon and post again here when I've heard back.
The woman also said they've had quite a few enquiries about the show. So it looks like there's definite interest and it sounds like the plans are coming together.
Watch this space.