There appear to be two methods of calculating Fajr timings, one being the One-Seventh of the Night method and the other being Angle-based method. I live in England and there are drastic differences for beginning of Fajr because of these methods. The one-seventh method says fajr starts at 4am while the angle-based method says it starts at 2am. Please advise what I should do as softwares are being contradictory!