Drill size disparity between DRU and webpage

I’m having trouble with routing a BGA with 0.8/1mm pitch using the DRU file provided, even after decreasing spacing between tracks. The minimal drill size in DRU is specified as 12 mil while on webpage drill size is 0.2mm-6.3mm. What is minimal VIA drill size?

The DRU assumes that the minimum drill hole size is 0.3mm (12mil), since this is what works for most customers. But actually, we can make 0.25mm and 0.2mm drill holes in the standard service which usually cost a lot more. In your case you may need to opt for the smaller drill hole option to get the BGA to fit. Sorry for the confusion!