I have (so far) seen a pattern of the GrubHub credits not posting until the statement is issued, but GrubHub is not (for me) a "merchant offer" it is a monthly credit that is supposed to come with the card. With respect to redeemable merchant offers, I've had two credits post within a matter of days, and one that they are now telling me may take up to 2 billing cycles. The variance suggests to me that Citi is waiting to get "reimbursed" from individual merchants and then passing on the credit to customers rather than just crediting the customers' accounts once a qualifying purchase has been made. But whether that is the cause or not, the variance in expected posting times makes the promised credits much less valuable, as it requires prolonged attention on my part.