That way you can work on a 2017-18 team and make trades with 2017 picks at the 2017 draft. At least until the 2017 draft is over.
I liked this idea too and when I make a thread for next season I do it manually. In the comments I write like 2017 First Round Pick #20 (Player Name) for example. I would like to see it changed too but if they don't you can do that.