Funny, I was going to make a post requesting this last night, but got lazy.
I created a custom topic called "Downtime Activity". All downtime activities allowed in my campaign from the Players Handbook, Dungeon Masters Guide, and Xanathar's Guide to Everything have a subsection with fields applicable to those subsections.
I don't want the campaign time line cluttered with hundreds of downtime entries. I have on topic per character per downtime period. Problem is that for longer periods, their may be multiple weeks of a specific downtime activity. I would love to be able to just create a section for each instance. Instead I kludge but putting all roles and dates in a notes snippet and then just enter the totals in the fields. Example:
2019-02-11_17h30_09.jpg
I would rather have a new section to record each instance / week of an activity.