If you have a few months to spare, do a search in this forum on "break-in" or the hipster term "burn-in." Go make a sammitch and grab a Dr. Pepper, because you're going to be doing a lot of reading.
As usual, Max has a nice, measured, pragmatic response. My view is a speaker will sound 99% of what it will ultimately sound like after 30 minutes of vigorous playing. Many people think break-in has to be done every time you fire a system up (for maybe 5 minutes), and I believe temperature and humidity of the room make an even bigger difference. In any event, after a half hour, the differences are miniscule, and acoustical treatments will make a far, far greater difference.
And there is no reliability or long-term performance issue with break-in of a speaker, as there is with an automobile. The suggested break-in period of 500 miles for my '08 car was expressly for break-in of the differential; not the engine...although the car continued to run better up until it had 7,000 miles...(coinciding with the purchase of the 2nd set of rear tires.) Speakers have no metal-on-metal movement to "break-in."