I'm almost positive this applies for music only but then again, I never did try to download apps. My friend and I share our music. We built my iTunes collection together, so when I got iTunes match she of course needed to have access. So when she signed out of the "store" and tried to sign in with my apple ID, it said that her Apple ID was already associated with another device (her iPhone) and had to wait for 90 days to re-associate.
So, I tried everything I could to get around this because she should get access to my music and enabling iTunes match already deleted her music. I logged into her account and saw her device and saw that there was 90 days remaining. I tried to "remove" it so that I can associate it with mine. I was able to remove it, but I tried to log in again with my Apple ID in her iPhone and still said the same thing. The device "re-attached" itself. So, the remove option doesn't work if there is a X days remaining. Seems like Apple was doing to appease some record labels or something. That's what I read online.
Anyway, she had to wait 90 days. Re-download iTunes music and re-sync. Then on the 91st day, it finally worked. Now, her Apple ID is on my account with a X days remaining.