Eurotunnel has released the following statement: 

07/11/2019 - 10h00 CET

Please note that we will be carrying out exceptional maintenance works in the tunnel overnight on 10/11/2019 as of 23h00 CET. These works were not planned but are necessary and cannot be postponed. This will result in an amended timetable between 23h00 and 0700 CET. 

An amended timetable is available on Eurotunnel's website.