Saw what I assumed was a formation of aircraft lit up flying West to East

Saw contrails behind the clouds and then a formation of what I thought looked like aircraft flying West to East. It took about 40-60 seconds to cross the sky where I was before I lost sight. I do have trees on both sides of where I was sitting/standing. They were lit up with what appeared to be soft white lights, don't remember seeing any other color lights. Almost looked like a caterpillar formation. Did not appear to me that they were that high in elevation. Had my hot tub running so I did not hear any sound. Same line of flight that I saw a group of aircraft flying single file spaced out one or two to a slot, that was about 20 aircraft and was early morning earlier this spring. Again, I assume both of these instances were military aircraft.