I don't think a full break-in as you describe is necessary. I rotate speakers in a 2nd system quite a bit and have found that after sitting idle for a few months or even years, the speaks take 15-30 hours to settle into their sound. This could be the materials becoming compliant again or most likely, the electronics stabilizing but you do not need as many hours as with the initial break in.
BTW, I find the same is true with amps, preamps, etc. If a piece of gear has been sitting on the shelf for a couple of months, it may only take an hour or so and SS tends to take about twice as long as tube gear, in my experience. Any gear that's been idle for more than 3 years, should be brought up on a variac just to avoid any possible damage/heartache and the break in will obviously be longer - still just hours though.