Did anyone else see strange GA4 Realtime behavior yesterday?

As part of a test we’re currently running, we’ve been closely monitoring the traffic of one blog. Yesterday, we noticed something unusual: throughout the day, GA4 Realtime consistently showed roughly 100–200 active users at a time. Yet when we checked the data today, there was virtually no corresponding traffic recorded for August 31.

That leaves an interesting question: where did all those Realtime users go? Was this another GA4 reporting anomaly, or was it automated traffic that appeared in Realtime but disappeared from the final reporting?

There is at least some recent precedent for treating the reporting-anomaly hypothesis seriously. Search Engine Roundtable documented a GA4 Realtime reporting issue on August 19, when multiple users reported missing or abnormal Realtime data before the problem appeared to resolve after several hours.

That does not confirm that Google Analytics experienced another outage on August 31, and the spike itself could still have been bots or other automated traffic. GA4 Realtime is also not designed to be treated as a perfectly stable final dataset, so the discrepancy is worth observing before drawing conclusions from it.

Still, the difference between what appeared in Realtime and what we can see today is large enough to be noticeable. If you were monitoring GA4 yesterday, did you see anything similar?