WSCC300

I live in southeast Michigan. I had my Radioddity G30, hand held out on the back porch to just listen. I listened to two people just 25 miles south of the Mackinaw bridge which is 300+ miles from me. Today I heard two people talking from Indiana, and two others from Cleveland. Are they somehow jumping from repeater to repeater? I'm sure someone has a answer to quell my curiosity. Thanks for helping me understand...