The present study helps to understand the local combustion characteristics of PREmixed Mixture Ignition in the End-gas Region (PREMIER) combustion mode while using different natural gas-hydrogen blends. In order to reduce NOx emission and diesel fuel consumption micro-pilot diesel injection in premixed natural gas-air mixture is a promising technique. New mechanism for n-heptane and natural gas has been developed based on GRI 3.0 mechanism for this study. Main focus of the simulation is on end gas ignition detection, knock intensity, effect of hydrogen on end gas ignition and emission predictions. A new simulation model is created using G-equation flame propagation model with detailed chemistry in order to detect end-gas ignition in overall low temperature combustion. This combustion simulation model is validated using extensive comparison with experimental data for dual fuel engines and also is compared with well established flamelet combustion model.