Before I start trading gold futures options, I have a question. First, I understand what day these options expire based on the contract month. But what time of day is the last trade accepted? Reasons for confusion: Globex trading hours 6:00 PM-5:15 PM EST. Floor 8:20AM to 1:30 PM. Settlements prices are quoted at 11:30PM. So, what time of day do these options expire? Thanks.