Bug with SharePoint Events?

One of my page admins reached out to me because she was adding events to a communications site, and the events were not showing up on the full list of events. I re-added an event for Oct. 31 three times and it still wasn't showing up when viewing all the the events between April 15 and Dec. 31. But, if I narrowed the range to July 1 to Dec. 31, it suddenly showed up (four times!).

As I worked with it more, I realized that the site's "all events" view, which also pulls in events from our main company calendar, wasn't showing any events after Oct. 15, even when the date range went through the end of December. But then, I zoomed out and viewed the page at 80%, and magically all the events through the end of the year were visible. At 100%, they aren’t visible.

But then, still at 80%, I reloaded the entire site and went back into the "all events" view. Same issue: Oct. 15 was the last date that would load (end of page). But if I zoomed in even further, suddenly they became visible. 

Surely this is a weird bug. Any insights out there?