You also they often have very common procedures for these types of letters, right? Usually brought on by court cases, etc. For example:

http://www.fda.gov/ICECI/ComplianceManuals/RegulatoryProcedu...

They also generally warn of fines ahead of time, because otherwise they get people arguing due process.

Seriously, this is not that uncommon. Note the fine warnings in all of these special orders:

http://www.documentcloud.org/documents/1349845-n-h-t-s-a-spe...

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&c...

http://www.safercar.gov/staticfiles/safercar/recalls/Special...

http://www.autosafety.org/sites/default/files/imce_staff_upl...

etc