The new firmware will have reset the 'fuel gauge' chip - it will take several days of use to recalibrate according to your usage. The unbranded firmware has to be tested and certified problem-free against all networks before release; that's at least five in the UK alone. When it does roll out, I also expect it to be staggered to avoid network congestion or corrupted downloads. The update will be the O2 firmware, in that case. .... but won't be tested and signed-off. XXLPQ will be what they received from Samsung with clearance to test and release.