Premiere parties after ballet performances

[SwissBalletFan]

In preparing for my trip to see Polunin and Zakharova in Ratmansky's Sleeping Beauty at La Scala on 26 September, I notice that it is the premiere performance.

 

In Zürich Opernhaus, there is a premiere party on the stage after the performance which is open for the general public to meet the stars and hear the speeches etc. with free drinks and food (an inside tip maybe )

 

Initially I would like to know if anyone knows how La Scala party after premieres and if they are open to the public as I would of course love to see the stars etc. Does anyone know? 

 

Also how do the other ballet companies handle premieres and partying