Sun glinted and flashed off small object, disappeared then reappeared same spot 5 min later, impression was that it was chevron shaped

While watching a little league game at location, my eyes caught glint of sun or flash from an object in sky at 1:45pm. As I watched it move in place, looked like a white or silver bar/cylinder and was near due south. There was not much movement, but the object did change its aspect to my eye (glint/flash, then I could see some movement). After it disappeared, I remained in same spot watching game. Object reappeared at 1:50pm, I called wife and others to look but they couldn't pick it out. Each sighting was 5 seconds duration, object did not reappear the rest of the day. Sky angle was approx 45 degrees midway between horizon and zenith. Reference point was ball diamond backstop, and neither it or myself moved. Estimate the object was miles away and could have been a few thousand feet up (no clouds for reference).
Conditions: 85 degrees with a cloudless sky, object was far enough from sun that I did not need to shield eyes to observe. Wind approx 12-15 mph from S or SE. Someone suggested pelican or raptor riding thermals. Intensity of flash/glint was more intense than what would be possible with a pelican's white wing tips. Escaped birthday balloon? How could it have stayed in same location given wind speed. Quad Cities airport was near, but flights observed during the day used east - west approaches. No jet landed within minutes after the sighting, esp from that direction.
I am 62, an amateur astronomer, trained SkyWarn spotter, and eBird regular contributor. I see small flocks of pelicans all the time around my home.