poster is referring to gigantic rally at Pontiac Silverdome TODAY that was rescheduled after the Detroit Pistons' stadium proved too small for the event (presumably that was to be THURSDAY when first contemplated)
The rally was actually planned for Joe Louis Arena. It was never going to be at the Palace. The Palace's sound system isn't functioning.
DC Advance decided not to have it at the Joe because the Lodge is closed. There will not be 80,000 people at today's rally at the Silverdome and it was not the first choice or the optimum choice.