If there is an order, I’d expect it be outline order. I tried your described scenario, using 3 sibling notes:
Each note has a $StartDate os 1 January of the note’s named year. The timeline looks like this:
If I give ‘1960’ an $EndDate of 1971 and for ‘1970’ I set 1981, I see this:
If I now move ‘1970’ ahead of ‘1960’, I see the following which suggests OutlineOrder is used to decide vertical order:
The apparent placing of ‘1980’ is efficient use of space common to any timeline plotting I’ve seen. If I extend the duration of ‘1960’ to 20 years, we see outline order still being used to order the plot.
With the same 70/60/80 outline order, I can give the notes different bands. ‘1960’ $TimelineBand remains the default 0 (zero): the top band. ‘1970’ is set to 1, ‘1980’ to 2. We now get this:
You don’t. You have to work with the limitations above. Be aware a timeline view is not like a map: you can’t manually force the drawing locations. Depending on the degree to which entries ‘physically’ overlap on the timeline—or don’t, the normal horizontal event packing efficiencies may start a new ‘column’ of enticed such that, as above ‘1980’ may sit above ‘1970’. I’ve used a variety of Timeline tools and they all have this same limitation/efficiency (depending which way you see it) to the layout of the timeline.
Here’s my test file, for reference: timeline-test.tbx (89.3 KB)
See more on Timeline view here: Timeline view.