What do you think Jesus is trying to tell us here on Mar.13:18? It makes it sound as if His people have the option of changing the times as to when the time to flee will come during the great tribulation.
In Mark 13:14-19, Jesus was saying what a dreadful time the flight from Judea will be at the start of the Great Tribulation. He was advising those who will be involved to pray it won’t take place in the winter because conditions in the mountains of Judea during the winter could make such a trip very treacherous. Remember, He told them not to even take the time to get a coat.
The way He said it could mean that while the Great Tribulation will definitely come, their prayers could influence when it begins so as to make their flight a little easier.
Or it could mean something like, “You had better hope this does not happen in the winter time” as if to underscore how difficult their flight will be.