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I would work under the assumption that the AU would disappear. Since it's not "your" card, there's no reason for the CRAs to keep them on. If they do, great! but that's both at the mercy of the CRA & the financial institution (also why they report different - some bring all of the history with them, some don't).
As for closed accounts - honestly, just close them when you need to. I always vote for closing an account with fees if it isn't needed, and just ignoring any card that isn't used that has no fees. I throw them in a literal box (firebox) and "lock" the card when available. EX's monitoring is good at noting when a dormant card is used, so I just keep an eye on cards. Some people here advocate for closing a card whenever you're done with it for reasons (like preventing fraud), but I'm a fan of keeping as much history as possible. I don't do what some people do re: throwing a small charge on it every 6 months to keep an account "active," but I don't close them early, either. Do whatever is more comfortable and safe for you and don't sweat the closed account history too much.
@calyx I totally agree. I won't close a card unless there's an AF. I would put it away and freeze it if poss
possible. I probably won't bother making a small spend unless it's one of my older cards.