On Saturday next week (Nov 30 2019) I’ll upgrade this servers operating system. So the print map services will not be available for parts of that day, and maybe also for parts of Sunday Dec 1st
The main reason for this upgrade is that this will bring in Mapnik version 3.0.22, which includes one important improvement:
SVG PolygonPatternSymbolizer vector patterns will now finally be included into rendered PDF maps as true vector data, instead of converting them into rather low resolution bitmaps first.
This will finally make them look at least as good as in the rendered PNGs, which is especially good for generating large scale prints on paper.
See the cementery symbols in this example for the visual improvements, the blurry ones on the left are from the current public server, the much sharper ones on the right from an already upgraded internal test instance: