ISUK:
Interesting. AdBlue is something that is only used in Europe on heavy commercial vehicles to ensure engines meet EU emissions directive limits. It is certainly not used on car diesel engines here at present but would account for the shorter service intervals you have been quoted.
My Audi TDI uses AdBlue. There are warnings long before it runs out, so as to give time to top it up.
If it runs out the car doesn't start which would be a big nuisance. The workshop top it up on every opportunity to avoid this eventuality.
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"Form follows function"