Apple Music re-downloads all previously downloaded songs after iOS update. How can I avoid this in the future?

[iRube]

Apple Music re-downloads all previously downloaded songs after iOS update.

The latest iOS update caused Music to re-download all of the songs I had previously made available offline. This also occurs when temporarily signing out of my account. Thousands of songs and hours of time, not to mention a network drain.
Can I avoid this in the future somehow? If so, how?
Thanks.