Pheww, January 5th is over! I wonder why the deadline of so many schools were jammed on the same date.
Many people here seem concerned about the punctuality of the recommendation letters, so I wanted to share my experience with recommendations. As a round 2 applicant, my experience with Darden is limited, but I can tell my impression from schools I applied during R1.
A late arrival of recommendations and other supporting materials is usually tolerated, if the actual application was sent on time. Partially, the reason for the tolerance is practical - the admissions committee has to physically match your application with supplemental materials that do not arrive in the online package, such as the official test scores, official transcripts, and recommendation letters sent via regular mail. The next few weeks at the Admissions Office is filled with this basic chore.
If your letter(s) arrive during this "chore" period, you should be in for that round.
As said, I am no expert for the Darden in particular. And surely it is better for your letters to be in in time. But if they are late by few days, I think the odds is good that you are in.
Hope this help!