@david555 to be honest I do not know - it may be a limitation of the LEDs used or the controllers but from memory I do not remember the problems with the backlights being as obvious on firmware 3.105 which the TV shipped with but I didn't have as much HDR content to test on that version.
I'm waiting to hear back from the MD correspondence team and hopefully this has been passed over to the technical support guys to make it's way back to factory (the 3D issues have been passed through that channel now). I don't know how many other avenues this has been passed to Panasonic UK via now but I've read the link has been sent in via the support channels and dealer networks so thanks to all helping the cause.
I also read this morning that Nicolas over at HDFever may write an article around these problems to help our cause too so thanks for popping the link over there @david555 (merci très beaucoup Nicolas, je vous dois une bière

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