At first, we thought it might have been some sort of mistake. The transaction page isn't in the habit of breaking news, but it turned out to be right on.
NFL.com's Ian Rapoport reports that Manning made a minor alteration in his contract that was indeed submitted to the league. There was no pay cut or extension, but it was procedural. Manning and the Broncos altered language that involves his insurance. Rapoport notes it was the team protecting itself in case Manning suffers an injury, and the quarterback signed off on the change.
Any time a contract is altered in any way, it must be submitted to the league. It will have no effect on salary cap or any of the important aspects of his deal that runs through 2016.
That was a long way of saying: Mystery solved. Move along, nothing to see here.
Update: Yahoo! Sports on Sunday cited a source with knowledge of the contract details in reporting that the new deal will change the Broncos' salary cap situation somewhat.
Follow Gregg Rosenthal on Twitter @greggrosenthal.