Well ! Farish,
Around 15 candidates have expresssed their consent to be the party in the said pettition, while similar number of candidates have preferred to stay anonymous. the Date for next hearing is deliberately left confidential, only known to the pettitioners. However, there is no harm to make it public, but it should be substantiated by all those concerned.
Well !
Referring to the second part of your question as to how one can join the proceddings as a necessary party, there is no bar to join the pettition/litigation at any stage of the case before the judgement is pronounced.

Any one interested to be a party, can contact Muhammad Ali Awan advocate, himself an affectee and member of this forum.

Profound Regards,