On 29 August, an Antonov AN225 “Mriya” landed at Brize Norton at 20:37 (UTC +1) after overflying Rotterdam, Colchester London and Cirencester. Brize Norton is a military base of the Royal Air Force.
On 30 August at 06:00 (UTC +1), the aircraft is scheduled for a flight towards Athens, most likely the airline will overfly Belgium (thanks Martyn Benson for the tip), as the airline isn’t really flying according to schedule Aviation24.be opened a dedicated forum topic where you can follow the flight schedule.
Follow the aircraft on Flightradar24: https://www.flightradar24.com/data/aircraft/ur-82060
You can see a remarkable recent picture of this unique aircraft by one of our members in our Contrail Spotting forum: https://www.aviation24.be/forums/viewtopic.php?f=25&t=64097&p=371666#p371664