Help! Not sure how to change the start weight.

SO I had my starting weight set at where I started and then I had a meeting with my Doctor and health coach and was given my daily goals which I then updated and since I weigh in with them every week I updated my weight at the same time (lost 7 lbs!!!) It wasn't until this past Monday when I updated with my new weight that I realized MFP had changed my start weight to the weight AFTER my loss of 7lbs. My graph/chart shows the drop but the tracker only says I've lost 2lbs. I realize all that matter is I know the difference but it would be so helpful to me on this journey to see the actual amount all in one place.

My question is: Is it possible to change the start weight without changing the current?