I believe it is a rolling total. So (assuming no prior uncredited spend) if one had $1500 spend between March 1 and March 31 there would be no Elite night credit. And then if one had $1500 between April 1 and April 30 there would be an accrued $3000 resulting in one night.

But what the agent explained was that if (using this example) your statement end date was May 3rd and on your statement you had a $3000 charge on May 2nd you would not get that night until after May 31st.

Why Chase has chosen to go with this system instead of one where each statement would clearly list Elite nights earned is beyond me, but I am still grateful we have this option to earn extra nights.