What is the priority of pre-market orders if there is an imbalance?

I was reading about it and have some question:

Suppose the equilibrium price is determined as 95 and there is an imbalance.

  1. If LIMIT BUY 97 has a higher priority or LIMIT BUY 99 will be fulfilled first?

  2. If the answer to “1” is “closer one to equilibrium price has higher priority”, is it possible to determine equilibrium price before 9:07 AM with some accuracy?

  3. If there are two orders from different clients at 98, which one has a higher priority? Is it first-come, first-serve basis?

  4. Does pre-market allow partial fulfillment? Articles on the internet have mixed opinions. Some say it does, some say it’s all or nothing.

  5. Bonus question: NSE says iceberg orders are not allowed. What will happen if we make them anyway to circumvent “4” restriction?