Endemicity basically means that the virus will continue to circulate in the human population and is not eradicated, but its pattern of spread and transmission becomes more predictable and more manageable. There are no hard and fast thresholds one way or the other. The R number, that reproduction number, when this happens, will likely hover around one, but that doesn't mean there couldn't be epidemics or outbreaks in the years to come. There may be some seasonality to the virus as well. A lot of the experts are anticipating that the virus will hang around and cause ongoing impacts on the human population.
On January 18th, 2022. See this statement in context.