Looks like it was fixed on 10/28, which is definitely a long turnaround since it was first posted 10 months ago. I suppose it took so long because it was a pretty specific situation (removing a notification while inserting one while hitting a 10 minute timer) but still, that just goes to show two things: the latest KDE has fixed a ton of bugs, even unusual ones like that, and KDE still needs more people looking at bugs so things like this can get a faster turnaround in the future.

If anyone does find something like this that isn't getting enough attention on the official bug reports, I'd suggest just mentioning it to a developer friend who uses KDE.