There are growing concerns in the United States that, if he loses the 2020 election, President Donald J. Trump will refuse to concede defeat and exit the office.
Regardless of who loses the 2020 Presidential Election, when will the loser publicly announce that they concede?
This question resolves to the date at which the losing candidate concedes that they have lost the 2020 US Presidential Election, as long as they do not explicitly rescind said concession within 24 hours. This candidate may do this in any venue so long as it is public (e.g. a Tweet will suffice). They may do so using any phrasing (so long as it is sufficiently clear that they have accepted that they will not legally be President on 2021-01-21).
For the purposes of this question, it does not matter whether claims that the election was unfair or rigged are attached to a concession -- any statement of the form "[Anyone other than Candidate X] won [the 2020 US presidential election] [...almost any other phrase]" is considered a concession by Candidate X.
ETA (2020-08-20): This question resolves as "> Jan 20, 2021" if the losing candidate does not concede before the 20th of Jan 2021.