The articles say that Kerry heard a message on his cell phone Saturday not that Kerry "received a call from Reeve on Saturday". Do you see the difference?
This is what the article says:
...Kerry said the last time he heard from Reeve was on Saturday, when the actor left a message on his cellphone
ON SATURDAY, WHEN THE ACTOR LEFT A MESSAGE ON HIS CELLPHONE.
It doesn't say, "disclaimer, Reeve may have left the message Fri. nite."
Others are not forcing facts, you are. It is pure speculation on your part that Reeve may have made the call other than Saturday.