Schwaab is the broker. It surprised the heck out of me too... Are you sure they aren't required to sell? What is the point of calling it day trade margin then? And saying it can only be used during market hours. It's bizarre that they would have it both ways.
Well, Schwab is an omnibus broker, like IB. They deal with many asset classes. Maybe you had other assets in your account they were using as collateral for your future position? Get on the phone with them and find out the deali-o
Ninjatrader: Our Intraday margin for the ES contract is $500. These intraday margins are available for nearly 23 hours of the day. Our Intraday margins go from 5:00 PM CST – 3:45 PM CST the next day. So you would get a longer time period with even lower margins to trade the ES.