Resolved -
An issue with stale cache caused some products to be associated to incorrect collection data.
This results in problems with the application of collection-based promotions.
Timeline:
The problem was detected on June 5th at 11:30AM CEST.
A fix was deployed shortly after.
All cache is up to date as of June 5 at 17:30PM CEST.
Jun 5, 18:05 CEST