Matte white PLA on the batch from 3 weeks ago has had reports of black flakes in the extrusion changing the colour of the white to a tinge of black mid print and sometimes causing full hotend clogs, this has happened to 1 customer so far but its a very serious issue if it is widespread. If you have any issues with matte white from the batch 3 weeks ago please reach out as Im collecting all the rolls for testing.
The new batch and whatever is on sale at the moment is free from this issue, this is just impacting the 1500 roll batch that was sold 3 weeks ago