Is there any other way of speeding the download up other than performing this post midnight? I would prefer the option of having to download whenever it is required withou having to wait till nightfall. I didnt have this issue with previous ISPs where the download speed was 8meg (currently plusnet 20meg).
You could change to the Plusnet Pro product which gives line speed at all times, details here. Swings and roundabouts with regard to price and download allowance compared with the other products, Plusnet Value and Plusnet Extra. Expected speeds for all products and types of traffic are shown here.