I previously asked this question about what I might lose if I were to switch from iTunes Match to Apple Music. The basic consensus was that for my needs, I really wouldn't lose anything. I also found this question/answer which says as I understand it, that any songs I import to my library should be available on "all devices". Unfortunately now that I've lived with Apple Music for a while, I've come to a rather unpleasant conclusion. I believe I have now completely lost the ability to add new items to my iTunes library and play them from my phone.
My library is maintained on my home desktop computer, and also now partially on the cloud via Apple Music. I don't store songs locally on my phone due to limited storage space. Previously with iTunes Match, I was able to play anything in my home library from my iPhone 4s which is running iOS 8.1.2 (and I'm not willing to upgrade to iOS9 and suffer possible performance hits as well as application compatibility issues, nor am I willing to upgrade to a newer phone because they are too stupidly big). Now however, it looks like anything that was added to my library prior to my Apple Music subscription, is still playable remotely. But anything I add to my library now, is not.
So am I right that since I now subscribe to Apple Music and not iTunes Match (and paying a whole lot more now, I might add), that my iOS8 phone can no longer stream any newly-added songs even though I've made them "available for download"? They do appear on my phone but are greyed out and cannot be played.
Best Answer
OMG I figured out what's happening, and I'm horrified.
If the song in question is available in Apple Music, then that song will be automatically treated AS an Apple Music item and therefore will NOT be able to stream even after being added to the iCloud Music Library, on any device running an OS older than 8.4.
So to be clear... music that I created myself that is 100% original (say something out of Ableton Live, Logic Audio, etc.) will be able to be streamed to my phone running iOS 8.1.2. BUT (and I just did this myself so I am 100% positive it is correct), say I rip a song myself from a CD (or download the song from any other website, etc.). If I add that song to my library, it will appear as an MPEG Audio File (or aac or m4a etc.) and be able to be added to the iCloud Music Library, but if that song is also available in Apple Music, then it will NOT stream to my phone!
Additionally, (and this is the really horrible part)... if I remove the download from iTunes, and download it again from the cloud, it downloads an Apple Music DRM-encoded file instead!
The old MP3 (or whatever) version is still on my hard drive, but the iTunes reference now points to their DRM-encoded Apple Music version, and it will not be playable in anything but iTunes.
I'd like to believe this is a bug, but I have a feeling it's intentional. iTunes never used to do this, and in my opinion this is pretty nasty... if I hadn't caught what was going on, I could have ended up with a substantial portion of my library all being converted into Apple Music files instead of the MP3s, AACs, etc. that I already have.
UPDATE: I'm on the phone with Apple now and it's confirmed. Apple Music without iTunes Match will not allow streaming of any newly-added and matched content, to any iOS device using iOS prior to 8.4. Also Apple Music will always replace any matched songs (even if you ripped them yourself from a CD) with DRM-encrypted versions, should you ever download them from iTunes Cloud (paying for iTunes Match would prevent this). So basically it's $25/year to remove DRM for good from non-Apple Music files.
I'm amazed I didn't run into this when I investigated using Apple Music in the first place. I understood that music I actually download through Apple Music (as an Apple Music AAC file) would be DRM, but to lock down my own CD rips if I ever need to download them again!?!? Brass balls Apple. Brass balls.