When I had leaks like that, it was the seal at the back door hinge. The leak hits the film that's already in the take-up area.
For more, see this thread
Col. Sebastian Moran, ret. (not really)
SLR, dSLR, and compact RF's. Black Yashica RFs; Nikon & Contax/Yashica SLRs; Nikon digital.
Where did all these cameras come from?