Eyewall Regeneration (Replenishment) cycle - the eyewall shifts, breaksdown and reforms as it rotates and as conditions vary.
Not quite...and it's Replacement, not Regeneration or Replenishment.
About two threads ago I posted a guide to ERCs and some of the mythology around them, I forget where. Anyway, a new eyewall forms surrounding the original eyewall (thus forming a bullseye) and the inner eyewall gradually fades away; the pressure rises some, and the maximum winds drop, though the area of high winds gets wider. Eventually the inner eyewall vanishes completely, and you're left with one eyewall..the new, wider eyewall. If the conditions for the storm are still favorable, this outer eyewall shrinks and the storm restrengthens again.
The entire process takes 12-18 hours. The 5AM NHC advisory noted the beginnings of it, so it likely began at 4AM today. Recon still shows concentric eyewalls but the inner eyewall is almost toast. The cycle will likely be completed by midnight or so.