My Show: Date Change on Sort List?

I have streaming shows on "My List" from Netflix and Amazon that I placed there many months ago without watching any of the episodes. Every now and then, one of these TV series (ie., Star Trek) will find it's way to the top of My List for no particular reason.

Of course, in the world of TiVo software (which is foreign to me) I realize there is an explanation for everything. I'd just like someone to shed some light on this...

 

Yes, it is the folder dates for these streaming shows which seems to be updating, bringing them to the top (most recent) of "My Shows."