Thanks! Perhaps one of the sites that track train delays can give a statistic?
This list doesn't have anything that looks relevant: https://www.rijdendetreinen.nl/en/disruptions/archive?date_b...
The day does not appear as an outlier in the monthly statistics: https://www.rijdendetreinen.nl/en/statistics/2025/10
I don't find a detailed statistic on the overall delays, but the per-station statistics for Amsterdam Centraal say 5% of trains were cancelled and 17% were delayed by 5 minutes or more (mostly by 10 minutes): https://www.rijdendetreinen.nl/en/train-archive/2025-10-29/a...