I recently registered on the YOTEL web site and received the following response from them this week.

Many thanks for taking the time to register your interest in YOTEL.

If the build plan goes to schedule, we hope to open Gatwick at the beginning June, and Heathrow in August.

Our website is in the process of being updated and will be relaunched in the next couple of weeks. It will include more up to date photos of the types of cabin available and an online booking facility, where you'll be able to make a reservation for the date and time slot you require.

In the meantime, we'll add your details to our database so we can keep you up to date as things progress and we're able to confirm an actual opening date.