That's fine. I was wondering what the prefix means. We don't have an actual standard naming scheme for in-game screen shots that don't fit the "name.png" "Grid name.png" or "name ig.png" formats. I'm okay with SS being the prefix of some sort but this type of discussion on making a standardization for screenshots would be better off on the forums. I'll make a topic on it if you want to add your thoughts on it (I'll edit this post with a link when i make it). One thing I will make note of is, my current scheme for screenshots, which is a bit overly complicated, is naming them in the fashion of "ModName - Name - ExtraInfo.png" which gives a bit more detail of the thing in question without being too extravagent of a file name but I feel this is cumbersome and could be cut back a bit.
As for the current images, that is fine. I have no issue renaming them and gives me something to do in downtime after having reviewed edits for the day or whatever. Just as long as it isn't being done on purpose, a few accidents here and there are fine too as it does take time to remember some guidelines.
Edit: Here is the screenshot image name scheme thread: Forum:Screenshot Images