M1 was washed in early December and after that cleaned two times with
CO. The ALFOSC zero point measurements (until the end of February
2012) indicate values similar to those shortly after re-aluminisation
of the M1 in July 2009. Unfortunately, the reflectometer from the
Liverpool telescope we have been using is broken and we do not have
recent reflectivity measurements of the mirrors. However, the results
from the zeropoint measurements are sufficient positive and we decided
to postpone re-aluminisation of the mirrors we were considering for
this summer.