lenders are, at the end of the day, a law unto themselves. we have recently remortgaged and got into a bit of a cash flo crisis because our original lender did not add the ten days between our completion and the date of our first monthly payment onto our first payment. This meant that when we remortgaged, it gets tagged onto the end. The lender that we are going to does charge you the odd days between completion and the date of the first payment straight away on the first payment date so last month we in effect, paid 3 months worth of mortgage in one month. It was a nightmare.
Chazza, you might want to check that when you remortgage, or sell ( if you ever do in the future before your mortgage matures) that you don't have the same thing happen to you and those few days tagged on the end.
I don't know what the difference is between exchange and competion is though, they seem a much of a muchness. buenchico on here might now, he seems a bit of a legal beagle.
hope this helps.