Since updating to 8.4.1 my battery life has become dismal. When looking at battery usage it shows 55% of battery has been used by Messages Low Signal. I cannot understand this as I'm not sending loads of messages and the battery has gone from 100% to 38% in 7 hours with 2 hours usage. I have checked the battery capacity and it's at 1400 mAh out of a possible 1430 mAh so nothing really wrong with the battery as such. I usually get easily 24 hours of standby with around 5-6 hours of use, but I'm struggling to get 12 hours at present. Has anyone come across this before, I've not moved location and have a perfectly good cellular signal.