Pin content or freeze while scrolling

I’m looking to prototype a page where content is pinned/unpinned at specific points in scrolling. For example, a date freezes in a calendar while events within that date continue to scroll. The effect is demonstrated here:

It feels like a straightforward behavior but I haven’t been able to find any examples or documentation in my hour-long search. I hope I’m missing the obvious but I’d love help in finding a solution.

Use Drivers and the keyframes there to set start and end points on the y axis for the elements you want to control by scrolling.

Note that you’ll need to group the contents you want to scroll and set that group to Scroll Vertical in the dropdown above the layers.

Thank you for the demo gif! I feel I might have been overcomplicating it. Your approach feels more straightforward than how I started tackling this. Looking forward to digging back into it. Thanks so much for your help!