E/C was never intended to be cycled. Clen was never intended to be used chronically, but instead only as needed.
People, (not you Steve) often confuse E/C with Clen because they both involve the beta-2 receptors. Clen is a potent specific agonist to the receptor and causes rapid downregulation of the receptor. E/C is NOT a specific agonist, but instead works in a round about way to increase circulating norepinephrine and epinephrine. The caffeine is also an adenosine inhibitor.
It has been demonstrated that E/C actually get more effective over time. This has been attributed to an increase in thyroid receptors.
E/C is notorius for rebound "hunger" though, so taper off over a long period of time, starting first with the caffeine, then the ephedrine.
For mild appetite control, ephedrine can be used alone with good results.