TimeStory version 1.5.1 was released on Oct 28, 2019. It follows 1.5, and was followed by 1.6.
TimeStory now uses your system’s language for all date labels, including weekday names and month names. The rules for abbreviating date labels have also been made a little more consistent, and the week view now includes month names for context.
(The following image was assembled from two screenshots, taken with different system language settings.)
You can now use File > Summary to get a quick summary of the size of your document. This includes the total date range, from earliest date to latest date, as well as the counts of events and sections.