Yes, and if you can't route to AMEX between 4:00pm-4:15pm, why show the quotes in SMART? If there is a quote in SMART, I expect to be able to hit/take it. For AMEX quotes between 4:00-4:15pm, this is not the case. Irritating.
Either they need to make AMEX routable between 4:00-4:15pm, or...