AMO orders in equity segment are sent to the exchange for execution at 9 AM.
Here’s how the pre-market session works:
If the order is not executed in the pre-open session, it’ll be carried over to normal market. If you’ve placed a market order and if it is not executed in pre-market session, it’ll be carried to normal market hours as limit order at the equilibrium price discovered in pre-market. So this order will execute in normal market at discovered price or better price.
While if you’ve placed a limit order, this will execute when the market price reaches the price specified by you. Until then the order will remain pending.