MLB & the Players' ASssociation has agreed to the following for 2021: DHers will be 7 innings; extra innings will begin with a runner on 2nd - carry overs from the 2020 season. Also players will wear trackable devices for COVID protocol as well as wearing masks & expanded testing.. I think the scheduling of games will factor in safety & distances - similar to what the NBA has done with its season.
I wish they would rescind the 3-batter rule for RP - and still don't like starting a runner on 2nd (maybe wait a couple of innings.