P0306 Code, the truth behind the fault?

Hi Jeepers. I’m new to this forum, but have the code P0306 misfire and diagnostic results suggest burnt exhaust valves on Cylinder 6, B’ bank. There’s a lot of chat across US forum sites as you’d imagine considering the population of owners compared to Aus, but does anyone know the truth behind the suggested design problem and the validity of the findings? I read that there was a design fault related to the cylinder head castings where the coolant channels were cast too small in Mexico’s manufacturing plant, between 2011/2013. Mines a 2013 but it has the later heads according to the date stamps, which should be good? My Jeep JK has run for the last 7 years in Qld AU, it gets hot 🥵 the coolant gauge has always sat just below normal regardless, so that’s 100%. Then I read it’s an inlet manifold design issue, therefor allowing the left bank of cylinders to run leaner than the right bank, so which is it? I’ve tried to web search wether or not I have a problem plenum inlet manifold or not, but can’t seem to find the relative information and part numbers to suggest otherwise? I have contacted the FCA but it’s a roll of the dice as to wether I’d get a replacement cylinder head, dependant on additional factors. The main one being my VIN NŌ is not on the computers list as a problem vehicle, yet it has the physical presence of the exact problem related to the respective service bulletin released related to Chrysler’s extended warranty offer?

I’m keen to hear if anyone can throw light on this one. It’s a well documented issue on US websites but I haven’t seen much on the Aus ones. I look forward to hearing the news and related links for me to follow up on, thanks!