Valentin gave an extensive overview of data/MC comparison work (before neutrino selection). Energy (track length*0.25) and cos theta distributions for muons/neutrinos showed good agreement.

ICRC ORCA-6 cuts were described - of the categories up-going, anti-spark, track quality, Cherenkov condition, containment.
Custom cuts were also shown which can replace the Cherenkov condition cuts. A reduction of the number of muons was shown, but also a larger disagreement in the energy with these cuts.

HRV was shown vs number of neutrinos - showing the anti-correlation trend. Periods of high HRV show better data/MC agreement but less neutrinos...

The generated spectra, divided by flavour, was shown. Potential issue with km3sim was discussed.

Lodewijk showed a binning scheme for ICRC in which an equal number of events were divided into each bin. The contour plot for fine v.s course binning was shown, and some additional features appeared under the new binning scheme. 
The systematic uncertainties, and a LLR of the model and null hypothesis were shown.

Bouke is working with the re-weighting approach to improve data/MC. Has had issues with parameter scan - due to starting value problem - but some insights provided by Stefan Reck.

BrĂ­an showed the data/MC agreement for an ORCA-6 run, with the MC produced using the new nextflow pipeline ran at Nikhef. An issue with a discrepancy in the number of muons from the light simulation was fixed by including the -k flag in JSirene.

Ronald showed a (worrying) plot from Jelmer, in which there was a jump/rise in the data rate, at about mid December 2020. This occurred at the same time as a T0 calibration (traceable in the eLog). There appears much more data than MC in a plot of data/MC rate vs time period.