We are all just guessing here .... they might compare your score against everyone in your zip code or you spending pattern against people in the same income range or ..... whatever they are doing it seems to be overly agressive
and we never know all the facts here anyway 50k limit with 16% utilization.... which could be one card is at 100% and everything else at 0% and so on and so forth
collect data points and try to offer advise but stay away from trying to explain why Chase does what they are doing