Bests & Worsts Reviews from Amazon

I dislike that when the new issue downloads it removes the previous, and after going through the Manage My Kindle instructions, find that I have to redeliver the previous issues manually in order to finish them off. I feel it's a real time constraint that I have to hurry up and read it before it disappears - ugh. And as I can't keep the issues after the max of seven (7), as much as I'm truly supportive of sci fi writers and chose the pay option to contribute to their careers, the library would be the same deal of borrowing on a time limit.