If the handbrake shoes are rubbing then on a bit of a long run the entire disk will heat up. But sticking slider pins or a sticking piston would cause caliper to heat up.
I had problems with squealing on my fronts when almost at a stop even after cleaning and re-lubing it would come back after a while. I also noticed once stopped when taking foot off pedal Ian's car was on slightest incline i could actually hear the pads sticking and feel a faint grumbling noise through the floor when they were releasing very slowly. I used silicone grease for the pins and ceratec for the pads which would be fine for around a month but would just wash off.
I've since came across proslip product which comes with 3 different products in there own separate tubes 12 pounds roughly on Amazon.
There is one tube used for slider pins one for where the pads touch the caliper and tube for where the piston and caliper touch the back of the pads.
There are videos on you tube where the guy explains why 3 different greases are required for the 3 areas of the brakes.
So far all the problems i was having are gone, at first i thought it was a sticking piston but looks like it was the movement of the slider pins and pads them self not releasing that was the problem. Just make sure you put the same amount of lube on each slider pin.