I uploaded my NCB in time, but four days later we received a letter telling me it hadn't been accepted as. the letter head wasn't showing on the screen shot - you'd think all I had to do was re-send it - a simple mistake, but instead they told me I now had to pay £800 extra for the insurance, on top of the £1,400 we were already paying. When I called them up, I was told their internal comms had now told them they could only accept NCB certificates that were uploaded within 7 days , even though our letter said we had 14 days. It went from bad to worse - we cancelled the insurance after repeated miscommunications from their side. You just don't want to be dealing with this sort of set up if you did have an accident.