sdsearch

Some people can churn it without restrictions, some people can churn it only if they close both the previous card and its master account, some people can churn only if they do that plus wait some number of months, and some people can't churn it at all.

And even the same people sometimes move between one of the above categories and another! (For example, for two of three applications someone was able to churn, and then suddenly they got denied under the same circumstances where they previously would get approved.)

And there's no way ahead of time to know which category Citi will put you in at this point.

Though for starters I think most people need to close both the previous card and its master account to even have a chance.