How to download past purchases from old Apple ID without waiting 90 days to switch back to new Apple ID?
There is no way to lift the 90 day hold without contacting Apple support. You might not get much traction there, but it's worth a try.


https://support.apple.com/en-us/HT204074


Turning on iTunes Match, Family Sharing, or Automatic Downloads, or when you download past purchases on your computer, iPhone, iPad, or iPod touch, that device becomes associated with your Apple ID.

You can avoid most of this by having a backup (eliminating the need to download past purchases) and the other items are easy to not inadvertantly turn on.