3D850 stuck in the nozzle
My guess is that  particular brand of PLA is changing state inside the nozzle as it cools. Quoting from the manufacturer's page, 


  Materio3D PLA uses the NatureWorks Ingeo 3D850 polymer, specially
  engineered for 3D printing. It is tougher and stronger than standard
  PLA and can be annealed for improved heat resistance and toughness!  


If the residual material in the nozzle cools slowly enough (at the end of a print) to anneal, then by design it won't re-melt at the same temperature as the raw filament material.   I would recommend changing your gcode so that the extruder hotend is held at temperature after a print completes, and making sure to clear the nozzle with an alternate type of filament before allowing the nozzle to cool.    

quoting from another page,


  To achieve a heat treat on a printed part, submerge in water (or bake
  in oven) at 200F for up to 30 minutes.


notice that's Fahrenheit, well below extruder temperatures.