Did you get a different letter than went to this and my other IDs, minimikimus you ?? All of the letters I received said the following....   "We also want to provide you with advance notice of the impending release of a new Express Post version of the 500g and 3kg flat rate satchels. These satchels offer a simple and cost-effective express delivery service for when you are sending urgent items to your customers. These satchels are planned for release over the coming weeks and we have enclosed some samples for you."

I have thrown my letter out but yes, that sounds about right but I'm pretty sure that mine also said something about them being exactly the same as the normal satchels. So I presume the "planned for release over the next coming weeks" means "do not use them until we announce" - they should have been clearer in my opnion.