When trying to create a "Chronology" diagram with the current plantuml jar (1.2024.7beta2) and the input:
@startchronology
title Chronology Diagram
[A: 2024-01-15 01:08:12] happens on 2024-01-15 01:08:12
[B] happens on 2024-01-15 13:08:12
[C] happens on 2024-01-15 22:12:08
@endchronology
I get on the console the lines:
value=2024-01-15 01:08:12
value=2024-01-15 13:08:12
value=2024-01-15 22:12:08
looks like debug output to me.
Also the generated image contains for the point A the date and time but for the points B and C it is just the bare point.
See also http://www.plantuml.com/plantuml/uml/SyfFKj2rKt3CoKnELR1Io4ZDoSa70000