In case you didn't realise - and I didn't - Birmingham Opera have quietly opened booking for their August world premiere of Stockhausen's Mittwoch aus Licht, aka 'The Helicopter Opera'.

The six-part work is unquestionably THE event of the otherwise quotidian London 2012 Festival. Given the cost and complexity, further stagings are unlikely, so this may be a true once-in-a-lifetime opportunity.

Only 275 places [UPDATE 21/6 - now 350] are available for each of the four shows (22, 23, 24 and 25 August). Opening night is nearly sold out but there are more tickets left for the others at the time of writing.

Tickets are £35 and payment is by Paypal only. There is no reserved seating.

Here's the plan:

• 4pm GREETING - audience promenades on it ways to attend the...
• 5pm WORLD PARLIAMENT - seated on mats and cushions (provided)
• Interval 20 minutes
• 6pm ORCHESTRA FINALISTS - seated on mats and cushions
• 7pm HELICOPTER STRING QUARTET - seated on chairs and moderated by Guest DJ Nihal
• Interval 20 minutes
• 8pm MICHAELION - seated on mats and cushions
• after which the audience promenades out through...
• 9pm FAREWELL
• 10.15pm ending