Anyone know how long it takes for Sky LLU to settle?

Been activated about a hour and the line is giving me 4 meg connection, so on the rare chance its a faulty line there must be another reason since I lived across the road 2 years ago(well a few flats along also) and got 8 meg as its just around corner from exchange, the person in the next flat is on Orange ADSL(not LLU) and gets the full 8 meg and his router reports his line capable of 16.5 meg(despite it just being an adsl line) and last year I lived in a flat just under a mile from exchange and had O2 ADSL and got the full 8 meg(which is a miracle concering O2 Access)

I am just confused as all the student houses I have lived in the last 3 years have had O2/Be LLU and each one has had full LLU speed same day(and thats 3 properties)