Please be aware the CME will be deleting UDS on Eurodollar Options tonight:

CME Group will be deleting all User-Defined Spread Instruments (UDS) on CME Eurodollar Options Market Segment 50 during today’s maintenance window, 5/30/2019. Any UDS with resting GT orders will not be deleted.
As a reminder, UDS instruments can be deleted midweek. When this occurs, CME Globex sends a Security Definition message (tag 35=d) with the instruction to delete the instrument with tag 980-SecurityUpdateAction=D (delete).
A tag 48-SecurityID value from a deleted instrument can be reassigned to a newly listed instrument within the same week; therefore, CME Group strongly recommends the client system process the Security Definition message(tag 35=d) with the tag 980=D as received.
If you have any questions, please contact the CME Global Command Center in the U.S. at +1 800 438 8616, in Europe at +44 20 7623 4747 or in Asia at +65 6532 5010.
The sender provided the following contact information.
Sender’s Name: CME Global Command Center
Sender’s Email: gcc@cmegroup.com
Sender’s Contact Phone: 1800 438 8616
Announcement from the exchange:

CME Group will be deleting all User-Defined Spread Instruments (UDS) on CME & CBOT AG Options Market Segment 60 during today’s maintenance window, 5/29/2019. Any UDS with resting GT orders will not be deleted.
As a reminder, UDS instruments can be deleted midweek. When this occurs, CME Globex sends a Security Definition message (tag 35=d) with the instruction to delete the instrument with tag 980-SecurityUpdateAction=D (delete).
A tag 48-SecurityID value from a deleted instrument can be reassigned to a newly listed instrument within the same week; therefore, CME Group strongly recommends the client system process the Security Definition message(tag 35=d) with the tag 980=D as received.
If you have any questions, please contact the CME Global Command Center in the U.S. at +1 800 438 8616, in Europe at +44 20 7623 4747 or in Asia at +65 6532 5010.
The sender provided the following contact information.
Sender’s Name: CME Global Command Center
Sender’s Email: gcc@cmegroup.com
Sender’s Contact Phone: 1800 438 8616
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The TT Support phone lines have been restored. You may now contact TT Support on any of the following numbers:
We apologize for any inconvenience this may have caused.
Date: 5/28/2019 6:22:48 PM
Number: CA014-19
Subject: TT Phone System Outage
We are currently experiencing technical issues with our phone system. To report an issue or ask a question online, please navigate to the Support & Education page of the TT Website and select Report an Incident.
We apologize for any inconvenience and will notify you as soon as our phone system is restored.
If you have questions, suggestions or information to share about TT product features and functionality, please visit our community page at community.tradingtechnolgies.com
We are currently experiencing technical issues with our phone system. To report an issue or ask a question online, please navigate to the Support & Education page of the TT Website and select Report an Incident.
We apologize for any inconvenience and will notify you as soon as our phone system is restored.
If you have questions, suggestions or information to share about TT product features and functionality, please visit our community page at community.tradingtechnolgies.com
Please be advised that Trading Technologies will be performing Global Phone System Maintenance on our phone lines at 17:30 CST. The phones will be momentarily unavailable at that time for about 2 minutes at the beginning of the maintenance and after it is complete.
If you have a pressing software issue during this time, you can open an incident via our website.
TT Issues: https://www.tradingtechnologies.com/resources/support/
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