When does one have a preview of new draft prospects? The league only has 3 regular season games left and one still does not have an idea of who is available.
And how long does one have to plan and draft?
And does free agency period, and renegotiation of contracts somehow interfere with the draft?
Sorry for asking so many questions, just want to learn
You can see the draft class directly after the week 16 game, or the final game of the season. Once that is done, there will be a draft class page available for viewing under the players/coaches tab.
Free agency is split into two periods in MFN - early and late. Early free agency is a five day period directly after the playoffs and end of season sim. It's main effect on a draft is how high positions will be drafted, because some free agency classes are pretty good or pretty awful. For this next season, our league will have the worst free agency ever, since most of its allocation contracts will expire in two years, and the rest will expire after that. The only free agents available then will be the ones cut from teams and the ones that are already there.
Some free agencies have really deep pools, like the one after the 2018 season will, because most allocation contracts will expire, and most teams won't be able to retain more than two thirds of their players. That said, there will be a ton of players to pick up in free agency, which means that if there are many DTs, and people who need DTs sign them in free agency, they may not be drafted as high.
That's really the only effect that is caused by free agency for the draft.
Once the end of season sim happens, you can also start making your custom draft board, but you will be able to see the prospects and their ratings for about 8 days before then. Between end of season and the final day of the draft, there will be a draft tab next to the players/coaches tab at the top of the screen.
Late free agency is a three day period after the draft, and doesn't usually have many good players. It's just the leftovers from early free agency.