Rookie draft beck spots

First time Commishing dynasty. After rookie draft owners have 2 weeks then they have to get down to normal 26 man roster. So they have room and can make moves do I adjust rosters and add say 8 bench spots and then in 2 weeks adjust back down? We are on Sleeper so if ur over roster limit you can’t make any moves until you are at roster limits. Hope I’m making sense. Thanks!!