Left half of screen flashing colours, right side fine, but flickers

I have an LG 55EG920V OLED TV and it has had minimal screen on time on its 3 year life, est. 1500 hours.

Turned it on the other day and left hand side if screen was flashing multiple colours, right hand was fine but had a slight brightness flicker. Images can still be viewed, bit exactly half the screen is flashing constantly.

Remote only turns tv on and off now, no menus load or input selections.

Is this a T Con issue or is it more likely main board?

P.S, does anyone know how to get the back off these TVs, think I've got all the screws but still won't budge