Further digging down now, I think you have a point, UK quotes Natural gas that's uncompressed, LNG will add more on those factors. So howarth LNG assessment probably makes more sense here.

However couple of things that bother me

1. Study compares domestic coal and shipped LNG, not sure how reasonable that comparison is
2. Japan is not pushing more capital on LNG, their stupidity is jumping directly to hydrogen/ammonia based economy

Also I am not advocating for starting new LNG based plants, any new investment should be towards renewables. But if there is flexibility of shifting loads between existing plants, one should prefer LNG over coal.