As a web developer, I'd say there's a potential plausible explanation for oscillating counts like this. If you have a few different caching servers that the election sites are frequently hitting to fetch data from, and somehow hit an old count, depending on how the servers are setup there's a potential to temporarily show old data until the databases get consistent. In order to prove this you'd have to examine the frontend and backend code. I'd put odds at this being the explanation at extremely small, but there's a possibility that something like this or other technical issues could be the reason.