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Are you referring to Auto~CLIs or Consumer Initiated CLI ? I have never tried to get more than one CLI at a time, but I guess you could ask them if you are requesting.
I think most CLIs are evaluated per account, so they may not do an across the board increase for all your accounts at once.
Citi has been changing their CLI policy a LOT lately. It used to be one soft INQ for ONE Citi card every 6 months, more than that would require a hard pull. However, others have said they have been HP'd on the first card. I'd call in to see if they'll increase your lines without a HP. The CSR can tell you if your account will qualify or not.
The online method is a crap shoot