It looks as though Sally might have started to incubate her eggs. She is spending lots of time just sitting on the eggs.
There are still 7 eggs in Box3. This would be consistent with Sally incubating.
Over in Box1, Meg is still laying. It looks as though there are now 5 eggs here.
Finally, in Box2, both females are incubating the eggs with very little friction between them. The egg cup is now so wide that one female cannot cover all the eggs.
Two years ago when we last had two females sitting on one clutch of eggs, eight of the twenty eggs did not hatch out. It will be interesting to see what happens this time.