possible satellite, but no scheduled viewing, and the object flash/glowed brightly for a second or two.

I do not know if this was a satellite or not. I tried to use J-pass to see if there would be any satelites viewable in my area at this time, and there were none due.
The light was traveling northeast (more north than east) high in the sky just north of the city of Rockford. To my eye it was the size of the stars it flew between.
The strange thing is that in the middle of my viewing it flashed brightly for a second or two. The flash was about 10 times the size of the object. The object kept traveling at a quick rate of speed in the same steady direction until out of eyesight.
The sky was very clear, it had stormed here in Rockford about an hour or two before and the clouds had gone by the time I was outside. The light actually was traveling in the direction that the storm had led.
No Iridium "flares" visible at the time indicated.  PD