Jonah Holmes is heading for Wales to join Top 14 side the Dragons after three seasons with Leicester Tigers.
The Professional Game Board said more work needs to be done before Premiership rugby teams in England can start training.
Jonny May will return to Gloucester after his move to Leicester produced plenty of tries but not much team success for the Tigers.
A five-week break has been implemented in the Premiership, with the Champions Cup and Challenge Cup quarter-finals pushed back.
Exeter Chiefs have returned to the Premiership summit, while Wasps and Saracens also celebrated victories.
England overlook Mako Vunipola as a coronavirus precaution, yet he will play for Saracens against Leicester Tigers.
Nemani Nadolo will be in Leicester Tigers colours next season after the Premiership club lured the former Fiji powerhouse from Montpellier.
Marland Yarde was in fine form as Sale Sharks went second in the Premiership table in style against Leicester Tigers.
London Irish handled challenging conditions impressively to win at Harlequins, while champions Saracens were too good for Sale Sharks.
Exeter Chiefs rallied in the second half against Sale Sharks, but the Premiership leaders still slipped to a first defeat since November.