so i found on nymex's website the expiration data for QM contracts: Trading terminates at the close of business on the fourth business day prior to the 25th calendar day of the month preceding the contract month. If the 25th calendar day of the month is a non-business day, trading shall cease on the fourth business day prior to the business day preceding the 25th calendar day. i'd just like some clarification on this: the 4th business day prior to the 25th this month is the 19th which is friday. so, positions should be exited by 5:15 friday to avoid trouble? what would happen if i held a short qm 10-08/long 11-08 spread past expiration? or would the better question be: how could i roll this spread into next month?