We have booked a quota of rooms for the night 14-15 December in the DESY hostel. Please arrange your own accommodation by applying via this web page, giving the key word "hadron colliders" (under the category "DESY group"):
https://guest-services.desy.de/hostel_in_hamburg/index_eng.html
https://guest-services.desy.de/hostel_in_hamburg/index_eng.html