All the panels that I have mounted have lost adhesion in some parts between the frame and the covering panel. This has resulted in buckling of the panel revealing the LED lights in that part.
The panels do get quite hot/warm to the touch around the perimeter where the LED bulbs are. So I am thinking that mounting these panels as close to the ceiling as I have
results in them heating up sufficiently to loosen the adhesive bond. I'd be very interested to hear how any of your panels are mounted and whether they are as close to the ceiling as mine.