Quite a Number of My Playlists Disappeared This Evening

I had quite a number of my playlists unexplainably disappear this evening. This is very unfortunate, as I am an active user of ITunes with many playlists that I've spent a lot of time on. One of the ways that I make use of playlists within ITunes is to categorize music for partner dancing (east coast swing, west coast swing, country 2 step, salsa, etc.). A number of these types of playlists were among those that disappeared today. As an example, please see the image below and specifically the red highlighted area. You will see that I have a folder labeled WC Swing and then several playlists within that folder. The problem is there used to be a lot of additional playlists in that folder until today. You can see that I have there playlists in the folder currently that involve ranges for BPMs (beats per minute). There are playlists for "91 - 95," "121 - 125," and "126 - 130." However, there were a number of additional playlists that I previously had in between and surrounding these ranges ("81 - 85," "86 - 90," "96 -100," "101 -105," "106 -110," "111 - 115," and "116 - 120") that as of this evening have disappeared. These were handpicked songs within these BPM ranges that I had placed in these folders based on careful evaluation of the songs and how they sounded for dance purposes.

This is only one example of playlists that disappeared. In a separate instance, I had a folder labeled Country 2 Step with a bunch of playlists based upon BPMs and other evaluation criteria. In the case of the Country 2 Step songs, the entire folder and every single playlist within it has disappeared.

This appears to be some sort of Icloud issue. The folders and playlists were all created locally on the computer that they disappeared from. I did not inadvertently delete them. They disappeared on their own.

I should say that I'm an iTunes Match subscriber (have been basically since they first started offering it) and have about 22,000 songs in my library.

I did try signing out of my account (and consequently deactivating ITunes Match) and then signing back into my account and reactivating ITunes Match. I managed to uncover a small minority of the playlists that had disappeared by doing this. However, I am still looking for a way to recover all of my playlists. Any suggestions, recommendations, or solutions would be greatly appreciated.

Thanks,

Ryan