Newcastle Falcons' promotion to the Premiership is set to be confirmed after the Championship season was concluded early because of coronavirus.
The Falcons have a 100% league record in 2019-20 and the Rugby Football Union has said the table will be determined by a "best playing record formula".
Yorkshire are set to be relegated from tier two, having lost every game.
The women's Premier 15s season has been declared null and void after 12 of the 18 rounds were played.
Defending champions Saracens Women led the table by two points from Harlequins in what was the final season before four of the league's 10 teams will have to re-apply for membership.
"We believe that the decisions made provide fair and balanced outcomes for the game and maintain the integrity of the competitions," said RFU president Peter Wheeler.
Newcastle will replace Saracens in the men's top flight, with the Allianz Park outfit's relegation already confirmed following persistent salary cap breaches.
It has not yet been decided how or when the Premiership season will be concluded.
The Championship's second-placed side Ealing were 18 points behind the Falcons with a game in hand and have said they would take legal advice should they be denied the chance to win promotion.
Newcastle director of rugby Dean Richards described any potential legal action as "distasteful".
"This has been a difficult decision to make in the most unprecedented of circumstances," added Wheeler.
"There is no single solution that will suit every club, but the approach taken is one that we believe best reflects the nature of league rugby in England.
"With 80% of the season complete for the community game, we believe our approach is fair and the right one for our leagues. We have clubs that are clear league leaders and worthy of promotion, but also other clubs who have said they would benefit from relegation, to play more meaningful rugby."