sb34 - sudden accidents, can be a sign of some sort of emotional turmoil, but one a day is not a huge crisis. I'm sure he is well aware of the impending upheaval, and that you are worrying about it too. Could he also be reacting to the lack of routine in his day, after playgroup and so on has finished? Maybe a summer playscheme, or a football course, or swimming lessons, or something for a week might give him a bit of routine and stability?
It's just a personal thought. My boys are having a wild summer - 2 wks here, 2 wks with grandparents, then 2 wks at new house with us - new county, new friends, etc., followed by starting school/nursery for both of them. They are well aware what is going on, and are a bit unstable and loopy at times. We are trying to give them some routine for a fortnight at least with swimming lessons in the mornings, and some summer playgroup in the afternoons. It seems to be helping them a bit.