And the email from FXCM.

Thank you for your interest in FXCM.

In continuation from our conversation. While not yet fully confirmed there appears to be an issue on our demo server and trades on US OIL taken after 22:00 GMT on Friday the 18th should not have executed.

Our tech team will review the error and attempt to rectify this issue by the next expiration date.

This issue did not effect any live servers. We apologies for any inconvenience

Best regards,