The land their current ground is on was owned by the Fullers family and was donated to them. There's still a big connection between them and the brewery, I've had some input into the set up at the new ground.
They have a huge issue though as they have agreed to leave the old ground end of this season. The lock down has caused delays but the biggest issue is that they are unable to get a safety certificate until there's been ramp up events held, and as we know no one is allowed to have any sort of large gathering. They may have to share if they get promoted as they may be able to extend their stay at the old ground but would not want to spend the money to make it Premiership standard (floodlights, tv points etc)
That depends on the state of play at the start of next season. If the PL season starts behind closed doors, then they would get a safety certificate for that, no problem.