A former officer of the RFU told me that the extra points were to ensure Sarries do finish bottom, as it has been pointed out that:
the regulations state the Premiership club which finishes bottom must be relegated, which could mean Sarries plus one other if Sarries didn't finish bottom. Championship clubs had already brought this up with the RFU.
Sarries, if they didn't finish bottom, must be allowed to play in one of the European competitions next year.
With regard to time to be spent in Championship, I found this on another site:
Darren Childs, the chief executive of the Premiership, predicting they (Sarries) will come straight back up. Looking to the next two seasons, the Premiership clarified on Thursday that Saracens, if they win the Championship in 2020-21, will need to make a salary certification in June 2021 that covers their year in the Championship, and a forecast for 2021-22. The current season 2019-20 would be immaterial.