> By cutting the sunrise-to-sunset fasting period of the day to a much shorter period. Actually, the first day of this IETF (and the last of IETF54) were very interesting for those fasting on the 9th of Av fast day and having to travel westwards. Flying west during the fast increases its duration, for example from Jerusalem to Vancouver there is a 10 hour time zone difference, so instead of 25 hours the fast increases to 35 hours without food or water. Y(J)S