I just received a batch of PCBs with the wrong size mounting holes  
The drill file clearly states they should be 5.2mm, but they are 6mm
The manufacturer now says that they have made it according to the mechanical drawing I provided. The affected holes have an outline* on this drawing and so,
according to ‘ancient rules of PCB manufacturing’ (says they!), this takes precedence over the actual drill file.
I have *never* heard about this rule and would be much interested to find out what the combined wisdom of the forum has to say about this.

*The outline is actually a keepout area I defined to get a bit more clearance around the holes. It ended up on the drawing by accident and I didn’t think anything about it when I sent the files out