Miniseries release date

For TV miniseries, the release year for most is singular e.g. ‘2024’. For a few, however, it’s left open, e.g. ‘2023- ‘. Why is that? Aren’t all miniseries one season long by definition? It doesn’t make sense to me to leave this open ended as it implies the series is ‘live’ i.e. there are more seasons to come.