Drum brakes hang/pop when cold

By cold I mean when sitting overnight and then operating, not below freezing temperatures. When I first drive my 93 ford (im sorry) explorer (so, so sorry) after it has been sitting for a couple hours, the rear brakes hang after depressing the pedal and will ‘pop’ off the drum after I go at least 6-10 mph. Seldomly, the front brakes will do the same thing and ‘pop’ spectacularly off the rotors after the wheels are spinning fast enough. After driving 5 miles, this behavior stops and the brakes function normally. The brakes are 100% brand new except the wheel cylendars in the rear and dust shields in the front. What could be causing this?

I would have someone with an ASE “BRAKE” certification inspect both front and rear brakes to be sure they are assembled correctly…

Granted I may not be ASE certified but I have done many brake jobs on my own vehicles over the past decade and I have never encountered this issue. I have had the brakes inspected and adjusted, and the ASE technician who drove the truck said they needed adjustment. He did the adjustment although the balance between the front and rear brakes seemed to improve lightly, the hanging issue never ceased.