I have rebooted (i apply the updates offline usualy), but it persists. I've also ran the apt full-upgrade and autoclean/autoremove with no luck. plasmashell version on the terminal also reports .10 version. It's just a silly little glitch in the UI it seems!
Don't know about kde, but it seems like the two things are looking at a different number. Maybe a release file vs package number or a library call.
You could look at dpkg/apt list and see if you have some packages with those version numbers. Maybe something didn't get through the queue in time. Especially since it's Sid.
Also, if it works, it probably doesn't matter what the numbers say.