Which Address to post the form if sending by special deliver

[deeaa1999]

Hi All,

The new 05/2011 version of the SET(O) guidance, mentiones two different addresses to post the form. One for ordinary post and one for courier. They also mentiones to do special or recorded delivery under ordinary post section with a PO Box address. But if I do a special delivery, somebody needs to sign and take the delivery. So then I should use the courier address isn't it. Please can anybody help on this one?

[geriatrix]

Post - First class, Second class, Special Delivery.
Courier - Royal Mail Sameday courier, DHL, TNT, UPS, and the likes.