I have made several damage to the leather strop in three days, but today my movements were fast without any cut in the strop.
I would strongly recommend to you that fast is the last thing that you want to do when stropping. Forget what you may see on videos. Instead of "fast", learn to strop "properly". "Fast" only gets you a rolled or damaged edge and a damaged leather strop.
Slow down and focus on performing the flip properly.
Good luck, keep up the good work.