And since it's been (typo!) into repair a few times my answer has to be no. If Samsung did have a fix it would have been cured. The curved models are also DEAD when it comes to backlight issues as well, you've read the priors just like me.
I'd dump it and move back to flat models.
I have a Ue55Js8500 curved, and in its history have had a few repairs. The final repair I still wasn't happy with and had insurance payout for it.
The issue is an outline box around the screen about 2-3 inch in from the edge. It shows up in various sources and in deferring light faint colours.
I've had a look online and some people have said it's the Lcd panel (would be unfortunate as it's had 4 in the repair process) some have said it's the blocking material behind the glass ( I'm a little be scared of tearing down but if need be, it maybe where the lights sit might need tape or the diffusion layer needs blocking?) and it could be the tcon board firing up the lights wrong.
The screen has also been blank screening when first turns on (sound and menu still works but the screen goes blank of what ever picture is on) so maybe in my thoughts a main / av board is to blame ?
Or could the issue be the famous led/colour banding ?

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