Hi Mick -
After the SILVER qualifying event is closed (April 8th, 23:59) the 12 top SILVERs will be contacted and asked to confirm their presence.
If not answering or declining, the 13th and behind will be contacted.
The SILVER grid will be confirmed just on-site (Saturday morning for Monza) and if SILVER class will miss any of the 12 elements, they will be replaced by the fastest AMs.
People eliminated from PRO and SILVER semifinals will be eligible for re-joining the queue and accessing in the AM semi-final if they'll be in the top 12 AMs (on-site challengers)
All of this to have the very top 12 drivers in the final, but not to prevent any new talent to come on site as an unknown guy and have success