Unfortunately I am no longer at the company where we used it. A former colleague would always sort it out - I (or one of my team) just told him what was needed and he called our account manager and people jumped!

There's an engineer free Monday afternoon (as I've told BT to cancel the whole thing, since they forgot to place an order for FTTC on the new line) .
Shame the free engineer (who will now have to go to McDonalds for his afternoon coffee) is in Oxfordshire!

It's completely area dependant, ie some areas have engineers booked up for 1 week in advance and some can have 6 week lead time.