Oil and Filter Change..

Hi again,
 
what is the reccomended milage to change the Engine oil and filters on a Td5 ?
 
Very new to Td5 engines thats why this question is so stupid lol...
 
Cya.. Thx too.. 
 
 

Every:
6k miles engine oil and filter
12k miles transfer box  and main gearbox check and top up
18k miles transfer and main gearbox change

If it was mine and if the car is used in anger much then I'd halve those mileages as oil is a lot cheaper than engines/boxes ;)