it's hard to see on this upload, you can clearly see it on my phone (the original video). at 0:20 you can see it flicker (reflect off the sun) to the left and a little below the plane's trail. It's like a piece of tin foil was just floating along way up in the atmosphere, but it was moving in a line. I'm sure there's a logical explanation, maybe a satellite, but I can't find anything to match it.
