One of the reasons most often given to disclaim that the resurrection of the dead and the catching away of the believers is on Rosh HaShanah is the statement given by Yeshua in Matthew (Mattityahu) 24:36, as it is written, "But of that day and hour knoweth no man, no, not the angels of heaven, but My Father only." Because Rosh HaShanah was understood to be the hidden day, this statement by Yeshua is actually an idiom for Rosh Hashanah. Thus it should be given as proof that He was speaking of Rosh HaShanah because Rosh HaShanah is the only day in the whole year that was referred to as the hidden day or the day that no man knew. 
 http://www.shalom-crmi.org/html/seven7.html
 
 

Kay