I can't say whether a renewal letter was sent, only that I didn't receive one - &, it was apparent they weren't prepared to send a duplicate. THAT is why renewing my membership, after various attempts, became more trouble than it was worth.
Most clubs go out of their way to keep on board those who's membership is about to lapse, not CCC though - just a rather curt e-mail saying I'd had my last magazine because I hadn't renewed. Ideal opportunity, I would have thought, to attach duplicate letter in case it was an oversight, the original hadn't been received/had been lost or even to give a second chance to those who might've thrown theirs away in a fit of pique - but, of course, that's not CCC's style it seems!
I suppose one day, hopefully not too late, it'll realise that it needs members more than members need it.