No, everyone in the past wrote letters to their friends in the present. These letters may have been the last communication they are able to give, since no one knows if they are going to be able to get back to the present.
True but this is their way of saying their last good byes and saying their feeling about one another. Thats what most soldiers do when they are about to go on a dangerous mission. They write a letter to their families and give it to a higher officer or good friend asking that if they don't come back to give this to their family. My dad had to deliver a few messages and ask his buddies to hold his letter to my family and I.
-fangirls-