Bookworm:
Hi. I have only just seen your post of 2nd November.
I was trying to provide practical advice to Long Final, rather that an a complete and verified accurate statement of his legal obligations, which I certainly could not provide. I did say that the information I provided was based on what I do.
The advice given to me by customs and special branch is at variance with the requirements as stated both in Jepperson 'Entry Requirements' and, as you say, the AIP.
The source of my information is:
Customs: A proforma 'General Aviation Report' provided by the CCU at Gravesend. The notes with this form asked for 24 hours notice. Gravesend was the unit interested in Cambridgeshire flights, prior to the NCU, and prior to Gravesend it was Ipswich, using the same proforma. The proforma has space on it for all the information listed in my earlier post. NCU have said, in a telephone conversation, that they are happy to accept details on this form and 12 hours notice is OK.
Special Branch: Around the anniversary of 09-11, Special Branch contacted Bourn and stated that they required details of all foreign flights. I was leaving for France in less than hour after their contact, I phoned for clarification. They confirmed the details on the CCU/NCU form were fine for them; that 12 hours notice was required, but less notice was better than none.
Although not directly relevant to this thread, SB Holyhead do require more information on their form and do require 24 hours notice.
It seems to me that it is better to cooperate with the requirements of SB and customs, whether properly promulgated or not, and on this basis I posted my reply about Cambridgeshire to Long Final. SB requirements, in particular, seem to vary around the UK.
I could also have said to Long Final that there seems to be no interest from customs and SB in the majority of flights, but he would not have thanked me if his flight had been the exception.
All the best.