Light leak: Camera technique or development technique?

I have a few photos from my first field outing with my first large format setup that have pronounced light leaks at the edges. I think they are from having switched the inner and outer baffle on my SP-445 during development, but I wanted to see if there is another possible cause (something to do with removing the dark slide, perhaps?). I think I have not had a problem since I put the baffles in correctly in the SP 445, but I wanted to see if this pattern looked familiar to others.

Attachment 207267

Full size: https://duke.app.box.com/file/713442837965?

It is faint, but it looks like the rebate got fogged, so most likely did not happen while the film was in the film holder.