have a look at
http://www.caa.co.uk/docs/3/20070601...OfPractice.pdf its the CAA's Code of practice.
Found it intresting reading when i was having a reg 6 appeal with them.
It contains this nugget "
Written communications will be replied to within ten working days"
But then follows it with
"
Of course, some communications and requests for information require
comprehensive responses which might take longer to prepare. In these
cases, we will acknowledge your correspondence within ten working
days. We will advise when you can expect to receive a comprehensive
reply and who may be contacted on the matter."
When i mention that i never had a response to any of my letters within in 20 days if at all from PLD to 2 members of the CAA board it caused a few reaised eyebrows from them.
Though i have found now that when you find a person in a department who is good, just speak to that person dirrectly. Hard at first but after a few (meaning lots) of calls you get to know who to talk to and cut out the dont know people.