Q: iTunes Match:You can use iTunes Match on this computer with just one Apple ID every 90 days. You cannot associate this computer with a different Apple ID for 85 days. What can I do?

Unfortunately you will have to wait 85 days.

I'm only guessing, but I suspect it is to stop people simply using all their friends iTunes match subscriptions and avoiding paying for content that they wish to listen to themselves.

I appreciate that, I think what you are seeing is an anomaly caused by the need for protection as required by the record labels in order for them to license Apple to use iTunes match.

I had this happen back in December/January. I sold my MBP that I used to subscribe to iTunes Match back in December. In January, I bought a used MB and tried to use iTunes Match on it. I was told I had to wait nearly two months to use it on the new computer. I waited and was finally able to use it in the new computer.\

Sadly, this has more to do with the content providers (Record lables / movie studios) than it has to do with Apple impsoing the restrictions.

I've just found this out myself, sold a MBA that I bought new last July only to miss it so bought a second hand unit and find that I can't use iTunes Match on it for 65 days... So until then I can only access my music via my iPhone or iPad wouldn't care if this was free but we pay a yearly fee for this.

I certainly will be thinking about this when I next renew my subscription.

I found out too: My SSD went down, installed a new one, and now I'll have to wait 62 days (originally 90). What a hassle