Well I haven't realxed since october (and believe me i need it). I stopped the frequency of my relaxers because i wanted to give my hair and scalp a break from the chemicals. I have a section in the back of my hair (the whole left right backside) which was burned in march and at first i would lose a few strands here and there, but by spetember It had broken to mainly 1 inch!!! I KNOW this is all from that ONE experience.
I'm basically giving my hair time to recover. I will begin relaxing again in late february b/c my hair has made positive steps towards recovery. (No more sore scalp, tender scalp areas, i've controlled 80% of my breakage).
I think that key to "waiting" any relaxer out (4ab hair apecifically, like mine) is minimizing the actual styling. Wearing the hair in stress-free styles like braid-outs, adrienne's ponytial method, and so on minimize the amount of weekly manipulation and doesn't stress the two hair textures, which means its less likely to break.
I know when i start relaxing again I will be doing so every 8-10 weeks OR whenevr i get 1.5-2 inches of new growth. Of course i'll try to wait it out, but i experience breakage (which i count as a setback). If at any time i feel i'm being too harsh on my scalp, i'll put my hair in a resting period.