Apple Music Questions about song matching across several devices

[NJRonbo]

I know all about iTunes Match where Apple essentially uploads your downloaded music library to the cloud and makes it available to stream on every device you own.

In the past, I thought that the only songs that could be matched were those that Apple had physically in its library.

But I noticed something today when I was accessing my music across devices...

All my uniquely downloaded music, stored on my iPhone, which is YouTube user remixes, extended versions, and songs ripped from rare CDs are now available across all my devices.

Is Apple now actually uploading all my personal music -- no matter where I got it from and how unique it is -- and making it available across all my devices? In other words, they aren't just matching what is in their library. They are storing all my music files?



If this is actually the case...

I have my ripped library of CD and YouTube remixed music stored on my iPhone. I'd like to delete it to gain more SSD space.

If I put it instead on my Studio or MacBook Pro, I take it that I will be able to stream all that music to my iPhone without actually having to use the phone's storage. Correct? Again, I would only do this if the first part of my question (top) is accurate.

Thanks for your help.